Q: Can a building official grant code modifications? Section 5109.3 is new and no language similar to it is found in the 6^th edition Chapter 36. One could interpret this language to give a building official a wide breadth of authority to grant modifications to the code. Can you provide some guidance on how this section applies?

A. This section should be used by a building official only in situations that do not lessen health, life, fire safety, structural or energy conservation requirements. This section may apply in the enforcement of Section 9305.1 where say the addition of habitable space in an existing basement is proposed. If a small area of the basement is slightly (about 1 inch) below the minimum height of 6’ 8” (exception 5) and if hardship is involved to change it, then the building official may use Section 5109.3 to allow the modification. So for issues associated with tolerances, this section allows the building official to make slight modifications to the code but still stay with its intent. It is important to note that “the details of actions granting modifications shall be recorded and entered in the files of the building department.”

Q. What projects require a building permit?

A:Most, but not all, projects require a building permit. See Section 5110 and the following table: Work Requiring HIC or CSL July 1, 2009 (127kb).

Q: Who enforces the code? Who enforces the State Building Code on behalf of the Commonwealth?

A. The Commonwealth employs approximately 14 state building inspectors who enforce provisions of the code for state owned and/or operated buildings. Municipal inspectors (employed by each city or town) enforce the code relative to all other buildings in their municipality. See Section 5107.

Q: As a CSL, do I need a HIC? If I have an unrestricted Construction Supervisor License (CSL) do I need to be registered as a Home Improvement Contractor (HIC) for example to add a deck to a 2-Family owner occupied house?

A: You need to submit the HIC application form in order to pay into the guaranty fund since the work is on an owner occupied dwelling per 780 CMR 110.R6.

Per Section 5110.5, an owner that secures a building permit for his dwelling is exempt from contributing to the guaranty fund (a fund to assist aggrieved homeowners). However, if a CSL does the work he is considered a “home improvement contractor” per 110.R6.1.2 and, per Section 110.R.2.4.1.2, is exempt from paying the home improvement contractor registration fee but must pay into the guaranty fund for work on owner occupied dwellings.

The logistics for CSL’s paying into the guaranty fund involve submitting an HIC registration form and only paying the guaranty fund fee. Forms are available on the DPS website: www.mass.gov/dps.

Q: What is the effective date for new CSL categories? When do the new Construction Supervisor License (CSL) categories take effect, and, can you be grandfathered in?

A. The new CSL categories are part of the7th Edition of the Code, 780 CMR for 1 & 2 Family Dwellings, which became effective on 1/1/08. However, the Board of Building Regulations and Standards voted to delay implementation of the subject CSL requirement until 7/1/08. You can be grandfathered in and therefore should submit an application demonstrating your relevant experience and qualifications before 7/1/08. Please keep an eye on our website for information regarding application as it becomes available www.mass.gov/dps.

Q: Does an Unrestricted CSL cover the new categories? I presently have an Unrestricted Construction Supervisor License (CSL). Does that license cover the new CSL categories effective with the 7^th Edition of 780 CMR for 1 & 2 Family Dwellings?

A. Yes, an Unrestricted CSL is sufficient to automatically grandfather you in for the new CSL categories without having to submit any application or other paperwork. See Section 110.R.5.1.2.

Q: What information is typically required on a Building Permit?

A: The standard State building permit application form for One- and Two-Family Dwellings can be found at this link BP Application for One and Two Family Dwellings Final (52kb). Municipalities may have their own particular forms but their forms must contain at least all the information that the standard State form has.

Q: Do I need a CSL or HIC to work on existing owner occupied houses with 1- to 4-dwelling units?

A: Click on this link Work Requiring HIC or CSL July 1, 2009 (127kb) for guidance on what work requires a Home Improvement Contractor (HIC) Registration or Construction Supervisor License (CSL) for existing owner occupied 1- to 4-family dwellings.

Q: Do the new CSL Specialty Licenses for Roofing and Windows/Siding permit structural work relative to roofing, windows/siding?

A: No, except as follows:

For Roofing: Work may include sheathing repair/replacement of up to 25% of the gross roof area and sistering 25% of the gross number of rafters in the roof.
For Windows and Siding: Work may include sheathing repair/replacement of up to 25% of the gross house exterior wall area and replacing damaged framing in window and door rough openings up to four feet wide

Q: Do the new CSL Specialty Licenses only cover work formerly covered by a Home Improvement Contractor (HIC) Registration?

A: The HIC Registration covered work on owner occupied dwellings of up to four units. The new CSL Specialty Licenses allow work on any type of structure up to 35,000 cubic feet, similar to the existing Restricted and Unrestricted CSL’s. Note 35,000 cubic feet is roughly equivalent to a 3500 square foot home or business.

Q: Do I need the new CSL Specialty Licenses for Solid Fuel Burning Appliance to repair and service such appliances?

A: No. A license is not required to repair or service the appliance, only. However, a license is required for the installation of the appliance.

Q: Does the Building Code have any language on warranties for construction work?

A: No. Language on warranties implied or otherwise, is not found in the building code. However, warranty language may be part of the contract documents between the contractor and owner (see for example Massachusetts General Law Chapter 142A. REGULATION OF HOME IMPROVEMENT CONTRACTORS, Section 2, Residential contracting agreements; requirements, item number (8): http://www.mass.gov/legis/laws/mgl/142a-2.htm

52.00 Definitions

Q: What is the change for wind borne debris regions? I understand that the BBRS has added some clarity to the definition of Wind Borne Debris Regions. Can you tell me where this can be found?

A. This change and other code changes can be found at the “Board of Building Regulations and Standards News” link on the Department of Public Safety homepage www.mass.gov/dps and is in the amended version of the code, 780 CMR for 1&2 Family Dwellings, effective January 1, 2008. Per the modified definition, a survey of the building site may be necessary in some cases to determine if a new home is in a wind borne debris region. But in those cases where a structure is clearly within, or outside of, a wind borne debris region a survey is not required.

Q: What is the difference between habitable space and living space?

A: Section 52.00 refers to the definitions of:

--gross floor area
--living space
--habitable space

They are listed in order of decreasing square footage. Section 5304 Minimum Room Areas has some language on how to calculate habitable space with rooms which have sloping ceilings.

53.00 Building Planning

Q: Is roofing and siding considered ordinary repair work? Section 5110.3 gives examples of work that does not require a building permit. Item #4 identifies “ordinary repairs” and goes on to include some further clarification. Historically most Building Officials require a permit for full roof or siding replacement particularly since the adoption of the HIC Law circa 1992. Now it appears even more important with the creation of licensures for roofing. Is roofing & siding an ordinary repair?

A. In general, full roof or siding work is not a “repair”. A permit is required except for repairs of a relatively small area of a roof or siding. Further, if this siding replacement or reroofing is not done properly it could impact, as noted in Item #4, the “energy conservation system” or “public health” of the building occupants. However on this same subject, there may be cases where a Building Official may not require a permit because of the limited risk to public health, etc. for example, roofing or siding of an accessory structure.

Q: Is a removable sash considered an emergency escape/rescue opening? I noticed that the emergency escape and rescue openings (5310.1.2 & 5310.1.3) are being changed to reflect those in the IRC.

A. Since most of the homes here in Massachusetts have double hung windows that means the minimum height will have to be approximately 5’-0” unless you take into account the sash can be removed without the use of keys or tools. Would you view the removal of sash as an operational constraint?

To achieve the opening size, removal of a sash is not permitted.

See code Section 5310 and the copied language below from the IRC 2003 commentary (on which the 7th edition MA code is based). A paragraph from section 5310.1 reads as follows:

“The required opening dimensions must be achieved by the normal operation of the emergency escape and rescue opening from the inside. Where a window is used as the emergency escape and rescue opening, then it must be the usual double-hung, horizontal sliding, or casement window operated by the turn of a crank. It is impractical to assume that all occupants can operate a window that requires a special sequence of operations to achieve the required opening size. While most occupants are familiar with the normal operation by which to open the window, children and guests are frequently unfamiliar with special procedures necessary to remove the sashes. The time spent comprehending the special operation unnecessarily delays egress from the bedroom and could lead to panic and further confusion. Thus, windows that achieve the required opening dimensions only by having a special sequence of operations performed upon them, such as the removal of sashes or mullions, are not permitted.”

Q: Do I need landings at all doors? I have a primary egress of 3’ at the front of home and 2’-8” at the back. That would make my 2’-8” door to the garage not counted toward egress and therefore a landing would not be required in the garage as long as the door swings into the home. Is that correct?

A. Please see Section 5311.4.3 Landings at Doors, Exceptions 1 and 2. Several different configurations (including one at least that may be without a “landing”) are allowed if the door is not a required exit door.

Q: Can I penetrate a fire rated ceiling with recessed lighting? I seek guidance on installing recessed lighting in the ceiling of the kitchen on the first floor of an up/down two-family dwelling. I understand that the fire rating of the ceiling must be 1 hr. Does Section 5317.3.2 apply in this case? For example, if each light box is less than 16 square inches can I install six of them (96 square inches total) in this kitchen which has a ceiling area greater than 100 square feet?

A. Section 5317.3.2 does not apply to ceiling penetrations. Therefore you must either use a listed (rated) recessed light or build a fire rated box for each fixture. If a listed light is used then “the penetration shall be installed as tested in the approved fire-resistance-rated assembly”. In either case the installation has to ensure that the required fire resistance of the floor/ceiling assembly is not reduced.

Q: How do you determine a building’s exposure category? I have looked at the definition of Exposure Category in Section 5301.2.1.3 and despite having read the definition numerous times I cannot determine the exposure category of the new home I will build. Can you please add some clarity to this definition?

A. This definition as written is the same as the definition found in IRC 2003, and it is not easy to apply. The International Code Council (ICC), the authors of the IRC and IBC, suggest that the definition in IBC 2006 be used instead to understand and apply the concept of exposure category. A Power Point file (which is found at the “Board of Building Regulations and Standards News” link on the DPS homepage www.mass.gov/dps) may add some clarity to the application of this definition. Some useful information before you get started is that in Massachusetts, most exposures are B, some may be C, none will be D, and probably none will be A. One should assume that the exposure is B and then determine (using the slides that follow) if the topography surrounding the structure suggest instead that it should be C.

Q: Can the WFCM be used for building a house in a 110 mph wind zone? I understand if a new home is built in a town in a 110 mph wind zone then the American Forest and Paper Association (AF&PA) Wood Frame Construction Manual can be used to prescriptively design it. I also understand that in some cases the home can be framed per the WFCM 100 mph Guide, if it meets certain requirements including but not limited to aspect ratio, roof height, number of stories, and exposure category (B). I heard that Massachusetts has a modified (WFCM Guide) checklist that can be used instead of the checklist at the end of the Guide. Is this true and what can you tell me about this modified checklist?

A:You are correct on the items that you have noted. MA has modified the checklist in several important ways. It can be found in amended Appendix 120.P or at the “Board of Building Regulations and Standards News” link on the DPS homepage www.mass.gov/dps. The MA version allows a roof with a pitch up to and including 8 in 12 to not be “counted” as a story. Further it does not require steel hold downs and straps in many locations if full height sheathing is used as defined in the MA checklist. Further, if the building will have furring strips installed in the ceiling abutting the gable wall then 2 x 4s installed on top of the ceiling joists are not required. There are other changes as well that were not noted here.

The MA version of the checklist was formulated in recognition of the highly regarded framing methods used in MA for many years and wood framing that has been used in North Carolina over the past 10 to 15 years which has performed well in severe hurricane weather in that state.

Q: What requirements must windows meet for new homes? I want to install windows in a new home. What specifications do the windows have to meet?

A. Each window must meet certain criteria with respect to energy conservation and wind loading and if the new home is in a 110 mph region and within one mile of coastal mean high water then additional wind borne debris requirements apply as well.

With respect to energy conservation and per Table 6107.1, the window must have a U factor that does not exceed .35 BTU/(hr x ft² x ^oF) if compliance to the code is met by using this table for the entire new home. The other approach is to use REScheck which allows some give and take between various components of the building envelope.

With respect to wind loading the DP for the window must be determined. All windows that are sold in MA contain a listing of its U-factor and DP. A Power Point file (which is found at the “Board of Building Regulations and Standards News” link on the DPS homepage www.mass.gov/dps) outlines the steps one may take to determine the DP for each window in the new home.

Q: Is there a standard way of measuring square footage vs. living space and how is the area of rooms with knee walls calculated?

A: Section 52.00 refers to the definitions of:

--gross floor area
--living space
--habitable space

They are listed in order of decreasing square footage. Section 5304 Minimum Room Areas has some language on how to calculate habitable space with rooms which have sloping ceilings.

Q: Can you provide me with the snow load designation for Hopedale?

A: There were several omissions on the new snow load table that was approved by the BBRS and effective January 1, 2008. In addition, since the new table was issued we have received several inquires that deserved consideration. Based on this, the BBRS Staff recommends that the following load changes be made to Table 5301.2(5).

30 PSF	40 PSF		50 PSF
Plympton	Egremont	Northhampton	Charlemont
35 PSF	Hatfield	Shutesbury	Washington
Belchertown	Hopedale	Sunderland	Worcester
Westfield	Leverett	Westhampton
	North Brookfield	Whately

Q: Can pull-down stairs be installed in the ceiling of a garage to access storage above?

A: Generally this can be done as long as the opening for the stairs maintains the fire resistance of the ceiling. This can be done in possibly several ways, two of which may be: 1) spray with intumescent* paint the exposed surfaces of the stair system in its retracted position or 2) install a fire rated pull-down stair system.

(*a material that swells and chars when exposed to flame and that forms an insulating fire-retardant barrier between the flame and material)

Q: Does the MA code require the landing on the exterior side of the required exit doors of a home to be no more than 1 ½ inches below the threshold?

A: The language in 5311.4 seems to indicate yes. However, the Staff understands the issues (water leakage under the threshold, etc.) that this may cause with typical New England weather conditions. The ICC seems to have been apprised of this as well and in an interpretation (no. 08-05 issued 12-29-05) addressed this issue. Their interpretation in the form of a Q and A is reproduced below:

Q: Does the Second Exception in Section R311.4.3, which permits the landing to be 7-3/4 inches below the top of the threshold, apply to all exterior doors, including the required exit door?

A: Yes. The required exit door is classified as an exterior door. The provisions of the Second Exception in Section R311.4.3 permits a landing to be placed a maximum of 7-3/4 inches below the top of the threshold at any exterior doorway, which does include the required exit door.

(Note that 2003 IRC only requires one exit door.)

Q: If a basement contains a sleeping room and other habitable space, does an emergency escape and rescue opening in the sleeping room satisfy the requirement for the other habitable space in the basement?

A: Yes. The second sentence of 5310.1 provides guidance on this. Basement sleeping rooms need direct access to an EER opening within said sleeping room. However, if a basement had one sleeping room and some habitable space, the EER opening within the bedroom would satisfy the requirement for the entire basement.

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Q: If a basement contains habitable and unfinished space would the emergency escape and rescue opening have to be located in the habitable space portion of the basement?

A: No. The code requires that each basement sleeping room has access to an exterior window or exterior door directly from them, without traveling through other adjoining or intervening spaces. Other habitable spaces in the basements of dwelling units can have the required exterior windows or exterior doors located anywhere. Since other habitable spaces are not bedrooms or sleeping areas, the fire awareness times and evacuation times should not be as significant. Therefore, the occupants can travel to other portions of the basements to access the exterior windows and exterior doors (including bulkheads per 5310.3).

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Q. Can spray foam insulation be left uncovered in basements?

A: No, in most cases. Refer to Section 5314 Foam Plastic for the provisions that govern the requirements and uses of this product.

Q: Can you answer several questions on the MA Checklist and the 110 mph Guide?

Q1: How should the MA Checklist for the 110 mph Guide be used?
A1: The 110 mph Guide is a prescriptive method for wood framing a one- or two-story dwelling in a 110 mph wind zone. The MA checklist (which is found in Appendix 120.P) can be used in place of the checklist on pages 27 and 28 of the 110 mph Guide. The guide can be viewed or downloaded at http://awc.org/pdf/WFCM_110-B-Guide.pdf.
Q2: Does the MA Checklist for the 110 mph Guide need to be met in its entirety to comply with the building code?
A2: Yes. The MA Checklist (see section 5301.2.1.1), along with the 110 mph Guide, is meant to be a prescriptive compliance “package” for framing a one- or two-story dwelling in a 110 mph wind zone.
Q3: If the 110 mph Guide and MA Checklist requirements are met, does this serve as a prescriptive means of meeting the requirements of the MA State Building Code?
A3: Yes, and the construction drawings do not need to be certified by a registered engineer or architect unless special design issues are present (design of structural steel beams, etc.)
Q4: Can the 5% additional full height sheathing requirement apply to wall lines with garage doors?
A4: Yes.
Q5: Can APA Narrow Wall Bracing be allowed to satisfy bracing for a garage door in a detached garage for example?
A5: Yes, refer to the APA-The Engineered Wood Association website on bracing www.apawood.org/bracing then register and view or download Whole House Wall Bracing (PDF 2.2 MB, free download).
Q6: Are windows allowed in an exterior wall where the stairwell opening is within two feet of this wall?
A6: Yes, as long as the requirement for full height studs is met (see page 10 of the Guide).
Q7: For a lateral addition does the aspect ratio, and other restrictions on the use of the 110 mph Guide, pertain to the entire dwelling or just the addition.
A7: The addition only.
Q8: Can you add some clarity for sheathing nailing per the 110 mph Guide for both a one- or two-story dwelling?
A8: The MA Checklist provides an attachment detail for full height sheathing. Based on input the BBRS staff has received from AF&PA, MA builders, and design professionals, an acceptable alternate attachment detail for full-height sheathing is provided for both a one story 1-STORY WSP Nailing (164kb) and two-story dwelling 2-STORY WSP Nailing (272kb).
Q9: If building plans, which are approved and stamped by a MA registered engineer or architect, are submitted does the MA Checklist need to be filled out as well?
A9: No. If the building plans define the wood framing requirements, with no reference to the Guide, then the MA Checklist is not required.
Q10: A contractor generated building plans using the Guide and MA Checklist and had a component of the building designed and stamped by an engineer. Are these plans allowed?
A10: Yes. If the general framing requirements comply with the MA Checklist and a component is engineered, then this falls within the intent of the code. Several examples of building components are headers, or floor or roof support beam(s) and girder(s).

Q: Are listed, rated shuttering systems allowed as an acceptable method for protecting glazed openings from windborne debris?

A: YES - The body of Section 5301.2.1.2 addresses glazed opening protection for windborne debris and requires that such glazed openings meet the requirements of the Large Missile Test of ASTM E 1996 and of ASTM E 1886 (Section 5301.2.1.2 goes on to recognize, as an Exception, that wood structural panels of a certain thickness and maximum span are also acceptable for such opening protection).

Where, however, tested, listed shuttering systems are manufactured to meet the requirements of the Large Missile Test of ASTM E 1996 and of ASTM E 1886, such shutter systems provide the same level of protection as the rated, glazed window system and thus it satisfies intent of Code to allow such rated shuttering systems placed over an unrated glazed window system and where the Code requires windborne debris protection – Code arguments for this allowance include recognition of Code intent and use of Section 5109.4.1 and where both demonstration of shutter listing to ASTM E 1996 and 1886 is provided and shutter anchoring over the otherwise unprotected glazed window is in accordance with the manufacturer’s requirements necessary to ensure shutter performance in the presence of high winds and windborne debris.

Q: Are ground snow loads used directly as roof snow loads?

A: No. For conventional construction, the 1 and 2 family code provides a prescriptive (using figures and tables) method to determine roof member sizes. The roof snow loads used to develop these tables are derived from ground snow loads.

The nomenclature and approach changed slightly from the 6^th to 7^th code edition to better conform to the International Code Council approach. This apparently has caused some confusion, but in both cases the steps are the same, for example:

In the 6^th edition you determined from maps which geographic snow zone your building is in and then found the appropriate rafter tables for that zone.
In the 7^th edition you determine from a table the ground snow load for the town the building is in and then find the appropriate rafter tables for that ground snow load.

Again, in both cases the rafter sizes are developed from a roof snow loading that is derived from the ground snow loading.

For non-conventional 1 and 2 family framing members or structures a registered professional must be used for design. The professional must use snow loads found in 5301.2(5) and use accepted engineering practice as per 5301.1.3, such as ASCE-7 methods.

For example, using ASCE-7 to find roof snow loadings, the professional must use the ground snow load from the table 5301.2(5) and apply appropriate factors to determine the roof snow loadings. Typically, the uniform roof snow loading is less than the uniform ground snow loading.

54.00 Foundations

Q. What frost protection is required for an accessory structure? I am finding it difficult to believe that frost protection of a foundation is required only on an accessory structure greater that 400 sq ft in floor area. It used to be 120 sq ft in the 6th edition. Would this allow for a 20 ft by 20 ft detached garage to be built on a slab? Also, would there be any wind requirements on the same 20 ft by 20 ft garage?

A. No, a garage needs to be on a frost protected foundation per a code change effective January 1, 2008. However, an exception to code sections 1805.2.1 and 5403.1.4.1, Frost Protection, does allow a 400 sq ft freestanding accessory structure to have an unprotected foundation. This does not mean though that a 400 square foot structure can be placed on, and unattached to, a slab or concrete blocks as one can see in Section 5401.2, Requirements, which states that “foundation construction shall be capable of accommodating all loads according to Section 5301 and transmitting the resulting loads to the supporting soil.” Clearly this can be achieved while not conforming to frost protection requirements, but it indicates that all foundations (including those for accessory structures) need to be considered with appropriate attention and detail to comply with the code.

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Q: Where does the Code cover sill plates and fastening?

A. See Section 5403.1.6.

56.00 Wall Construction

Q: Where is design of insulating concrete form foundation walls discussed?

A. See Section 5404.4.

Q: Can I install insulation board, in lieu of plywood, on the outside of an exterior wall?

A: For some portion of, or for the entire exterior wall, the answer can be yes, depending on the design.

For dwellings in wind zonesless than 110 mph, these sections may provide some guidance:

5602.3 Design and Construction…states that “exterior walls covered with foam plastic sheathing shall be braced in accordance with 780 CMR 5602.10”

5602.10 Wall Bracing…states that “All exterior walls shall be braced in accordance with this section”. It should be noted that there may be a need to have interior braced wall lines also; for this refer to 780 CMR 5602.10.1.1 Spacing.

5602.10.1 Braced wall lines…states that “braced wall lines shall consist of braced wall panel construction methods in accordance with 780 CMR 5602.10.3”

Table 5602.10.1 Wall Bracing…lists the amount and spacing of braced panels needed for each braced wall line.

5602.10.3 Braced Wall Panel Construction Methods…lists 8 different methods of constructing a braced wall panel. For example one method is method 3 which states “Wood structural panel sheathing with a thickness not less than 5/16 inch (7.9 mm) for 16-inch (406 mm) stud spacing and not less than 3/8 inch (9.5 mm) for 24-inch (610 mm) stud spacing. Wood structural panels shall be installed in accordance with Table 5602.3(3)” would be applicable for exterior walls while method 5, which states that “gypsum board with minimum ½-inch thickness placed on studs spaced a maximum of 24 inches on center and fastened at seven inches on center with the size nails specified in 780 CMR Table 5602.3(1) for sheathing and 780 CMR Table 5702.3.5 for interior gypsum board” would be applicable for interior braced walls.

Dwellings in the 110 mph wind zone fall under 780 CMR 5602.10.9 Design of structural elements…which states “Where a building, or portion thereof, does not comply with one or more of the bracing requirements in this section (780 CMR 5602.10) those portions shall be designed and constructed in accordance with accepted engineering practice.”

Available resources include:

the WFCM 110 mph Guide to Wood Construction in High Wind Areas and the MA Checklist or

the WFCM section 3.4.4.2 Exterior Shear Walls a. Wind Loads

57.00 Exterior Covering

Q. How can exterior siding be attached if wood sheathing is not used?

A: The Code provides specific prescriptive guidance on cladding attachment and allows you to attach cladding at 24” centers.

In the 7th Edition of the Massachusetts Building Code for One and Two Family Dwelling cladding attachment requirements are covered in Section 5703 Exterior covering with the majority of the requirements summarized in Table 5703.4 Weather-Resistant Siding Attachment and Minimum Thickness.

When sheathings other than wood or wood structural panels are used (such as foam plastic insulating sheathing), the code requires that the cladding be fastened back to the studs. The stud spacing is not specifically stated in Table 5703.4 and therefore other sections of the code must be referenced for acceptability of stud spacing. This information is found in Section 5602.3.1 Stud size, height and spacing in conjunction with Table 5602.3(5) Size, height and spacing of wood studs listing that studs spaced at 24” centers are acceptable for certain walls.

Depending on the type of cladding, thickness of cladding, and type and thickness of sheathing, different fasteners may be required. The penetration depth of the fastener into the stud is the basic requirement. For most claddings the fastener length is specified since the cladding and sheathing thickness is known, a minimum penetration depth is assumed. Where the sheathing thickness is variable (such as with foam plastic insulating sheathing), the fastener size needs to take into account the siding thickness and thickness of sheathing and still provide a minimum of 1” to 1.5” penetration into the stud. The penetration depth depends on the cladding type.

Fastener requirements for fiber cement siding fastened through foam plastic insulating sheathing are not listed in Table 5703.4. This table was updated in the 2006 IRC and now includes provisions for fiber cement to be fastened through foam plastic insulating sheathing back to the studs with a minimum 1.5” penetration.

In many cases furring strips are included in the design of the wall cladding to create a ventilation and drainage space behind the cladding. In this configuration it is often preferable to fasten the cladding to the furring strips instead of back to the studs. Unfortunately the code does not specifically cover this cladding system configuration so engineering may be required to design the cladding attachment to meet the cladding wind load requirements for the area.

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58.00 Roof-Ceiling Construction

Q: How do you choose rafter size under the new Code? I noticed that the snow loads have increased significantly in 7th Edition One- and Two- Family Dwelling Code compared to what they used to be in the 6th edition of the code per Chapter 36. Can you explain this and also provide some guidance on how rafter spans are determined and if the method is different than what was done using the 6th edition?

A. The BBRS voted on December 11, 2007 to lower the range of snow loads for the One- and Two- Family Dwelling Code to 25 - 50 psf. The range in the 6th edition is 25 to 40 psf. So some communities may see significant (25%) increases in snow loads. The BBRS is moving to adopting national codes and the snow loads that were approved reflect the loads shown in the IRC 2003.

For users of the code who wants to “prescriptively” choose a rafter for a particular snow load the methodology is similar to the 6th edition in that one may go directly to the family of tables (5802.5) and chose a rafter design based on Pg (ground snow load), span, spacing, species, and grade. The BBRS has approved a code change which allows use of the on-line Span Calculator www.awc.org/calculators/span/calc to choose a rafter design.

Additionally, a Power Point file can be accessed via the “Board of Building Regulations and Standards News” link which is found on the home page of the DPS website www.mass.gov/dps. This file contains some background on why lower loads were approved by the BBRS and shows some comparisons of rafter designs using the 6th and 7th editions.

Q. Where is guidance for roof mounting solar panels?

A: Section 5301.6, Roof Load, provides the required live and snow loads. Snow loads in Table 5301.2(5) have been changed via a code change effective January 1, 2008. Section 7301.2.2, Roof Mounted Collectors, provides additional guidance.

Q: Is venting required when insulation is installed between roof rafters?

A: In Massachusetts there are two ways that this can be accomplished. You can insulate the rafter space provided that you leave a ventilation space between the top of the insulation (typically fiberglass batts or blown cellulose) and the underside of the roof sheathing (Section 5806.1 Ventilation required). The minimum net free area of the ventilation space is described inSection 5806.2 Minimum area andSection 5806.3 Vent clearance.

Alternately, ventilation can be omitted from the assembly if one of the two methods described in the Exceptions of Section 5801.6 Ventilation required are used. These alternate methods install an air impermeable insulation to the underside of the roof sheathing (as with the use of expanding spray foam insulation) or to the top of the roof sheathing (as with the use of board foam plastic insulation). Both of these are types of closed-cell foam insulation.

In both cases, additional cavity insulation can be installed (typically fiberglass batts or blown cellulose) to increase the overall R-value of the assembly; however, the air impermeable insulation (either expanding spray foam or board foam plastic) must account for a minimum of 40% of the total roof R-value (though it can account for more) in order to manage the potential for condensation within the assembly. In addition, if the expanding spray foam insulation of rigid board foam plastic insulation has permeability less than 2 perms/inch, then a vapor retarder may also be omitted from the assembly.

Q: I want to install solar PV panels on my roof. How do I know if the rafters can handle the extra weight?

A: If the panels are attached in about the same plane (within 10^o) of the roof plane and therefore will not capture snow (drifts) then you may use the prescriptive tables for rafter spans, Tables 5802.5.1 (1) to (8). The dead load (psf) would have to be determined based on the manufacturer’s specifications for the panel weight coupled with the weight of the existing roof material. Use of the on-line rafter span tool http://www.awc.org/calculators/span/calc, which is allowed by the building code, is another method that will produce the same results as the table.

60.00 Chimneys, Fireplaces and Solid Fuel-Burning Appliances

Q: Explain “listing” versus “testing” for these appliances?

A: Typically these appliances must be listed. In general, ‘listed’ means that the equipment is included in a list of products published by a product evaluation/testing organization that is recognized by industry and building code officials. If a product is listed then the product was initially tested and found suitable for the intended purpose. Also, the listing organization routinely tests the product to ensure standards are met. Listed products typically come with documentation including the ‘testing’ standards met, and assembly, installation and operating instructions. For example, a factory built fireplace (780 CMR 6004) must be ‘listed’ by UL or a similar organization and it must be ‘tested’ to the UL 127 testing standard to meet the code.

Q: Can a pellet stove be installed into an unlined masonry chimney?

A: No. However, a pellet stove, which is a power vented, positive draft appliance may be installed into a clay tile-lined chimney cavity provided that it is a listed appliance, that the manufacturer’s installation instructions explicitly allow it and provided the chimney is lined with a clay tile and is in good, serviceable condition. See 780CMR6007.6 and NFPA211 section 6007.6.13 for regulations pertaining to natural draft (non-power vented) appliances.

61.00 Energy Efficiency

Q. How do you verify the R-value of a building insulation product?

A. Make sure it was tested in accordance with The Federal Trade Commission (FTC) Rule 16 CFR Part 460, Labeling and Advertising of Home Insulation and conforms otherwise to 780 CMR.

Background:

Many “newer” or” less conventional” insulation products are being offered to consumers in addition to the well established traditional products.
Submitted product R-values may be for floor, wall or roof systems rather than the material itself.

Often it’s unclear if the R-value test was appropriate and if it applies to the way a product is used (in the vertical or horizontal orientation for example).

Often non-standard terms like “average values” or “performance ratings” are used when presenting R-values.

The Federal Trade Commission (FTC) Rule 16 CFR Part 460, Labeling and Advertising of Home Insulation: Trade Regulation Rule, prescribes the appropriate tests to determine R-values for thermal insulation products. The Rule (a federal law) was issued “to prohibit, on an industry-wide basis, specific unfair or deceptive acts or practices”. It is incumbent upon the manufacturer to:

Provide the product label or documentation indicating the R-value was determined in accordance with 16 CFR.
Provide the test report with graphics showing exactly how the product was tested to ensure installation matches the tested configuration.
Provide the testing lab name.
Provide the lab certification documentation. Labs should be certified by the US Department of Commerce National Validation Laboratory Accreditation Program or comparable group.

Only R-values certified in accordance with the prescribed tests in FTC Rule 16 CFR Part 460 should be compared to prescriptive R-values in the State Building Code. See Section 6107.

Q: Do claimed R-values for foil faced/reflective insulation meet code? Products often indicate much higher “installed” or “system” R-values than the R-value of the product itself. Do these R-values comply with the Code?

A. The prescriptive R-values in the Code are for the insulation material or insulation system and not, for example, for the wall system with insulation in it. Reflective coatings can modestly improve insulation products performance but the R-value must relate to the insulation system as determined by standardized tests.

The insulation “system” R-value may be used per 780 CMR “6102.2 Materials, Equipment, and Systems Installation”. All insulation materials...shall be installed in accordance with the manufacturer’s installation instructions.”
However, “system” R-values must refer to the insulation system (insulation plus air gap for example) not the building component system such as a wall (wallboard plus air gap, insulation, sheathing, and siding) or floor.
Further, federal law requires that insulation R-values and insulation system R-values must be determined in accordance with FTC 16 CFR Part 460.

The insulation manufacturer should provide:

The direct as-tested R-value.

The standard test that was used (ASTM C-518, for example).
Testing lab certification per the National Validation Laboratory Accreditation Program or comparable group.
Test data that clearly explains what installation configuration the test simulated.

Some rules of thumb:

One inch of foam board is typically R-4 or R-5.
Foil facing does not improve R-values much unless there is an air gap.
With an air gap, foil facing can add about R-4 to insulation performance.
A 2-inch gap is optimal. A 1/8 inch gap is about R-0.5.
The air gap R-value diminishes rapidly beyond 2-inches as convection takes over.

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Q: If insulation board is installed on the outside of an exterior wall is a vapor barrier on the inside required?

A: No not necessarily. It is good practice to allow a wall assembly to be able to dry to at least one side. Most insulation boards are themselves “vapor barriers”, or said another way “highly effective vapor retarders”, and as such prevent drying to the outside.

Although Section 6106.2.1 Vapor Retarder reads that “an approved…vapor retarder….shall be installed on the warm-in-winter side of the thermal insulation.” Exception (1) reads “where it an be demonstrated to the satisfaction of the building official that the absence of a vapor retarder will not damage the materials or adversely affect the performance of the insulation due to moisture or it freezing.”

Most building officials accept International Code Council (ICC) prescriptive requirements. Reprinted below are changes that have been approved for the chapter on Residential Energy Efficiency in the International Energy Conservation Code (IECC). The BBRS Staff recommends that this latest work by the ICC, which provides some clarity on vapor retarders, be used as guidance. Section 402.5.2 Material vapor retarder class shows examples in each of the three classes. Table 402.5.1 shows different wall system configurations that work with a Class III vapor retarder (latex paint on gypsum board for example) in Zone 5 (all of MA).

Reprinted below:

IECC Language Approved in the 2006/2007 Code Development Cycle:

VAPOR RETARDER CLASS. A measure of a material or assembly’s ability to limit the amount of moisture that passes through that material or assembly. Vapor retarder class shall be defined using the desiccant method with Procedure A of ASTM E-96 as follows:

Class I: 0.1 perm or less

Class II: 0.1 < perm < or = 1.0 perm

Class III: 1.0 < perm < or = 10 perm

402.5 Vapor Retarders. Class I or II vapor retarders are required on the interior side of frame walls in zones 5, 6, 7, 8 and Marine 4.

402.5.1 Class III vapor retarders.Class III vapor retarders shall be permitted where any one of the conditions in Table 402.5.1 is met.

402.5.2 Material vapor retarder class. The vapor retarder class shall be based on the manufacturer’s certified testing or a tested assembly.

The following shall be deemed to meet the class specified:

Class I: Sheet polyethylene, non-perforated aluminum foil
Class II: Kraft faced fiberglass batts
Class III: Latex or enamel paint

402.5.3 Minimum clear air spaces and vented openings for vented cladding.

For the purposes of this section vented claddingshall include the following minimum clear air spaces. Other openings with the equivalent vent area shall be permitted.

1. Vinyl lap or horizontal aluminum siding applied over a weather resistive barrier as specified in IRC Table R703.4. (MA code Table 5703.4)
2. Brick veneer with a clear airspace as specified in IRC Section 703.7.4.2. (MA code 5703.7.4.2)
3. Other approved vented claddings.

Table 402.5.1 Class III Vapor Retarders Permitted For:

Vented cladding over OSB
Vented cladding over Plywood
Vented cladding over Fiberboard
Vented cladding over Gypsum
Insulated sheathing with R-value > or = 5 in 2x4 wall
Insulated sheathing with R-value >or = 7.5 in 2x6 wall

Q: Is there an Energy Conservation Application Form in the 7^th edition like there was in the 6^th edition?

A: It is not found in the code but the Staff received a form from a town building official that it is making available to the public and other MA building officials. It can be downloaded at Energy Compliance Form 7th Ed One and Two Family 02_07_08 (119kb)

Q: Why does REScheck ‘pass’ a building envelope U-factor that may not meet the minimum prescriptive requirements in the 7th edition Chapter 61?

A: When REScheck is used with the REScheck MA version of the code, the resulting building envelope U-factor may not meet the minimum prescriptive requirements found in Table 6107.1. This MA version is based on the 6^th edition of the MA State Building Code which is less “stringent” than Table 6107.1.

However, this may change. The BBRS Staff requested that the DOE create an updated MA version and received this response “After careful consideration, we have determined that it is not possible to support the (MA) amendments in REScheck….the required software changes will not support other states; and our budget to do this work is severely limited this year.”

The MA version will likely be removed from the REScheck code menu in July 2008,

If the BBRS adopts the IECC 2006 with the 2007 Supplements for the MA State Building Code, which is consistent with what NH and RI have already done. In the meantime, if compliance of a building envelope is to be done with REScheck the Building Official may suggest that the user select the IECC 2006 code. However, until 780 CMR is amended the user is allowed to use the still available MA code version of REScheck.

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Q: Is a vapor retarder required with open cell spray foam insulation.

A: Generally yes. Open cell insulation has a perm rating in excess of 1.0 (perhaps 2 or more) and as such is inconsistent with prescriptive vapor retarder requirements in Chapter 61. So, either (a) a vapor retarder would therefore be required or (b) the open cell spray foam manufacturer or engineer or architect of record or other would have to demonstrate that such is not the case and detrimental to the building.

Consistent with this Staff opinion is the 2007 Supplement to the IECC 2006. Included in this supplement are prescriptive vapor retarder approaches that may be proposed as alternatives. It should be noted that closed cell insulation products may preclude the need for Class I or II vapor retarders.

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62.00 Mechanical Administration

Q: To replace a furnace in the basement of an existing building, located in a flood zone, where must the new furnace be located?

A: Appendix 120.G501.7 and 120.G601.6 in 780 CMR directs the installer to place any new or replacement electrical, heating, ventilation, air conditioning and other service equipment above the base flood elevation or protected so as to prevent water from entering or accumulating with the system. During the permit process this flood elevation should be addressed prior to the permit being issued and during the final inspection.

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64.00 Heating and Cooling Equipment

Q: I would like to purchase a new heating appliance. How do I know if the product complies with the Building Code?

A: In general Chapter 64 applies. Additionally see Chapter 60 for solid fuel-burning appliances and if it is a wood burning appliance visit Wood-Burning Stoves and Other Solid Fuel-Burning Heating Appliances for guidance. If it is a gas appliance visit the 'Approved Plumbing Products Online System' offered by the Division of Professional Licensure http://license.reg.state.ma.us/pubLic/pl_products/pb_product.asp

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93.00 Existing Dwellings

Q: Are fire sprinklers required when renovating an existing dwelling?

A. The basic approach is as follows:

Determine if new construction of the same type of building would require sprinklers. If yes -
Determine if the renovation work provides an opportunity to incorporate fire protection easily. If yes-
Determine if the cost of installing the sprinkler system is substantial compared to the cost of the permitted renovation work.
Also, check Section 5313.5.

Regarding Item 1: Section 904.7 of the Code requires sprinkler systems for new three family dwellings.
Regarding Item 2: If the renovation work involves demolition of walls and ceilings for example, adding sprinklers might not cause much additional damage.
Regarding Item 3: There have been similar cases where it was decided that sprinkler costs in the range of 10% of the renovation cost were not considered substantial and therefore sprinklers were required.

Section 3410.0 Definitions discusses this under the definition for Substantial Renovations and notes that "the building official makes this determination".

Q: What Chapter, 53.00 or 93.00, governs for additions and replacement windows?

A. In general this table should apply:

Description	Chapter 53 or 93?	Comments
Horizontal Additions	53	Typically compliance of this construction to 53.00 does not impose significant cost or hardship.
Vertical Additions	93	If extensive renovation to the lower floor(s) is planned and compliance to 53.00 does not impose significant cost or hardship then 53.00 should be met.
Replacement Windows	93	Energy conservation compliance per 93.00 is required but 53.00 is not (DP and protection from Wind Borne Debris for example)
Sunrooms or Three-Season Rooms	53	If the main house is connected to the room via an exterior door or slider and no other openings between the main house and room exist (i.e. thermally isolated) then requirements for Wind Borne Debris do not need to be met.