A few times in the last year, our inspectors have run into a critical oversight that’s caused problems: incorrect placement of vapour barrier in floors over an unheated space.
First off, there’s a general rule on where vapour barrier goes: the warm side of the building. For things like walls and ceilings, that’s a really obvious thing. However, when building a stud floor over, say, an unheated crawl space – which is usually insulated later in the build than other sections – it’s easy to overlook the vapour barrier placement.
The image provided here illustrates how it should be done: vapour barrier is drawn over the joists before the sheathing goes down.
What some folks might overlook is the vapour barrier when building a suite over a heated garage. Garages are considered unconditioned (unheated) spaces, and for good reason: they’re often exposed to serious drops in temperatures, even if insulated and heated like the rest of the house. Further, garages must have a layer of vapour barrier encapsulating them to keep vehicle fumes away from the rest of the house. In this case, the old rule – vapour barrier on the warm side – holds true.
There is one critical exception: if closed-cell foam is used as the insulation. In that case, the foam serves as the vapour barrier, and can be applied on the underside of a sheathed floor without vapour barrier being in place.
In the past few months, our inspectors have noticed a number of situations where over-large holes have been drilled in framing members, or, alternately, holes have been drilled too close to the edge of a framing member.
We remind contractors of the relevant code on drilling holes through load-bearing elements:
184.108.40.206. Holes Drilled in Framing Members
1) Holes drilled in roof, floor or ceiling framing members shall be not larger than one-quarter the depth of the member and shall be located not less than 50 mm from the edges, unless the depth of the member is increased by the size of the hole.
Our inspectors have also observed holes for plumbing – usually for draining toilets or showers - drilled through the top members of open-web joists in the floor system below. This requires the contractor to contact the joist manufacturer for an engineer-approved repair, at the contractor’s expense.
If you have questions, give us a call. Our building inspection department serves rural Charlotte County, southern York County, and the municipalities of St. George, Saint Andrews, Harvey and McAdam.
This week, we’re going to give you a “pro tip” that will make installation of vapour barrier a whole lot easier.
If interior walls are going to be installed before the ceiling vapour barrier, staple a strip of vapour barrier on the ceiling where the wall is going to go before the wall is lifted into place. This gives a continuous barrier above the wood of the interior wall, and makes the later installation of vapour barrier a lot easier: it also means no worries about using acoustic sealant on that wall, because there is no need.
This simple trick ports over very nicely into more high-end construction where fire-rated drywall is required on the ceiling. In these cases, the drywall must be installed before the walls: failure to do so will result in some costly and time-consuming alterations after the fact.
Today, the Southwest New Brunswick Service Commission released new building or development permit application forms, replacing the older forms that were .... well, just a little old.
The new forms are easier to use, and also capture some critical information required to streamline an application process. There’s less to fill out, and less chance of a client giving us information that we don’t need. For example, we don’t need to know construction details for rural sheds or chicken coops – these are development permit structures that do not need to meet Code.
Do note that construction plans are required for all significant building permit projects. Plans do not need to be professionally created for small projects like home additions and the like – as long as our inspectors understand what you’re doing and can verify it will meet Code.
Also, site plan details are required for all applications.
The forms are fully digital: they can be downloaded onto your computer, filled out digitally, and emailed back to us as a complete form.
The new forms are available permit-form-v1-18022020 and are for all rural areas in Charlotte and southern York County, as well as the municipalities of St. George, Saint Andrews, McAdam and Harvey.
It’s our hope that the simpler, easier forms will reduce confusion for the one-time builder and streamline applications for the busy contracting firm.
If a permit is being filled out on behalf of a legal property owner, that owner needs to fill out an “agent authorization” form, available agent-form-19022020.
We had a question yesterday about shingles – that is, applying shingles to the side of a structure.
In this area, due to the heavy rainfall, one of the requirements for shingles is that it has what we call a “capillary break.” That’s a fancy term to describe a 1-cm gap that must be left behind the shingle and the housewrap behind. This is so that when (not if) water penetrates the shingle, it has a place to drain. There are two common ways to achieve this. The first is to apply a shingle backer, which looks like a scrubbing pad on steroids. The other method is to tacknail pressure-treated garden lattice on the side of the building. This also provides the required offset and breathing/drainage space.
You may ask, “why did you use the term ‘when’ water penetrates” the shingle? Shingles, like all wood products, absorb water. Even if there is no rain, but humid conditions, the shingle will retain moisture. If this moisture has nowhere to go, it will lead to mold and mildew behind the shingle, and begin to force its way through the housewrap and cause serious problems with the sheathing (and worse.)
And here, for your reading pleasure, is the Code on what kind of shingles to use on walls.
1) Shingles and shakes shall conform to
a) CSA O118.1, “Western Red Cedar Shakes and Shingles,” or
b) CSA O118.2, “Eastern White Cedar Shingles.”
2) Western cedar shakes shall be not less than No. 1 or Handsplit grade, and western cedar shingles not less than No. 2 grade, except that No. 3 grade may be used for undercoursing.
3) Eastern white cedar shingles shall be at least B (clear) grade, except that C grade may be used for the lower course of double course applications.
Questions? We serve the rural areas of Charlotte and southern York Counties, as well as the municipalities of McAdam, Harvey, Saint Andrews and St. George. We can be reached at 466-7369.
We’re starting to get the message out there that permits are needed for any new construction, even in “the country,” as some folks call the unincorporated areas. But our staff have noticed some confusion or mis-information about placing pre-built structures, including the (false) belief that no permit is required to move an existing structure onto a piece of property.
Here’s the key take-away: a permit is required to place any notable building on property.
(What do we mean by “notable?” In simple terms, it means nobody is going to be upset if you build Fido a doghouse.)
But the rules and permits required vary depending on what kind of pre-fabricated building one may intend to place.
These structures are built to very strict engineering standards and then placed on a foundation on-site. A building permit is required for all modular homes, but we only evaluate the permit cost based on the on-site work (concrete and finishing costs.) Inspections are required for the foundation and before move-in.
Modern minihomes are factory-built structures that meet specific engineering requirements. As such, they are exempt under the building code from requiring foundations. A development permit is required to place a minihome. Some municipalities have limits on where a minihome can be placed, so it’s best to call the development office for that municipality (for McAdam, Harvey, Saint Andrews and St. George, that’s us) for information.
Like minihomes, mobile homes also require a development permit to place on a property. And, like minihomes, most municipalities have limits on where they can be placed – if at all. Again, call first.
Other structures (shipping containers, etc):
Long-term storage units, like shipping containers or transport trailers with wheels removed are considered “structures” as far as provincial and municipal regulations are concerned. These will require development permits in rural areas, and either development permits or building permits (depending on size) for municipalities – if allowed at all. Once more, call first.
One of the challenges our building inspectors face is that some folks confuse our building inspectors with home inspectors. What's the difference?
A home inspector is usually involved at the onset of a real estate transaction. They are usually hired by a potential purchaser to evaluate the structural status and overall condition of an existing building.
A building inspector evaluates renovations, new construction and changes of use/occupancy. Their task is to ensure that the construction meets the National Building Code of Canada, including structural safety as well as life and fire safety. Building inspectors are usually employed by a government body of some nature, and have a certain scope of legal powers under the Community Planning Act, which also includes the power to work with municipal by-law officers in deeming buildings suitable for demolition.
In New Brunswick, a provincial professional association – the New Brunswick Building Officials Association - oversees education and certification of building inspectors, and the training meshes with a national body to ensure inspectors have similar training and qualifications across the country. All the inspectors employed by the Southwest New Brunswick Service Commission are active members in the NBBOA.
Earlier this year one of our inspectors was on site with a client to discuss a fairly simple project, but the visit identified a problem with the plan to shingle the roof. The roof, a simple single-plane sloping structure (“barn dormer” in building lingo) had a slope of about two feet over eight feet, (a 3:12 pitch) and the builder wanted to use shingles.
Veteran contractors may already know the problem our inspector identified: the roof wasn’t steep enough for a simple shingle installation.
The National Building Code of Canada stipulates that shingles can be used without much in the way of specialized installation for any roof with a slope of 1 in 3 (a 4:12 pitch for builders). Shingles can be used on roofs as shallow as 1 in 6 (a 2:12 pitch), but with special requirements, most notably that the installation must be such that there are three layers of shingle over the entire roof, not two as well as special applications of cement and tar.
Ultimately, the builder chose a metal roof, which is Code-compliant for a 1:4 slope, and for the builder, a simpler and cheaper alternative.
Here’s the thing with shingles: the shallower the slope, the more susceptible they are to issues of wind-borne rain driving up-slope.
Of course, shingle roofs require what we call “eaves protection,” (see post here: http://snbsc-planning.com/roofing-tip-protect-those-eaves/) and what builder refer to an “ice and water shield” when they transition over a heated space to an unheated eave. This helps protect the roof from ice-dams.
Every now and then, we field a question from a builder that requires a little more digging before we can give an answer. Earlier this year, one of our inspectors fielded such a question about a common practice: building a cantilever on a deck, such as in the image shown here.
The question itself was simple enough: “how far can I extend that cantilever?”
For those that aren’t in the building business, a cantilever is simply a building element that extends beyond its support, and when you think about it, cantilevers are common to just about every building: most roof systems extend beyond the support of a house wall, for example.
For a number of reasons, folks building decks want to extend the deck beyond the support beam. One of those reasons is that making a small extension does much to hide the same beam. But how far can a builder go?
Here’s the interesting thing: the National Building Code of Canada is surprisingly silent on cantilevers when it comes to decks. There is some guide for cantilevered construction supporting roof loads (max 600 mm/24” cantilever when using 2x10s, max 400 mm/16” when using 2x8s), but nothing about cantilevers when there aren’t roof loads.
So our inspector dug deeper and found documents from the Canadian Wood Council. This organization’s work actually feeds into the National Building Code span tables.
The exact same.
A Wood Council document (here) gives some very high-end detail about decks, but the take-away as far as cantilevers go is almost exactly the same: 400mm/16” for 2x6 or 2x8 lumber, and 600mm/24” for 2x10 or 2x12 lumber.
This question highlights how our office works: a question might stump us at the outset, but we’ll do our utmost to give a solid answer at the end. We serve the unincorporated areas of Charlotte and southern York counties, as well as the municipalities of Harvey, McAdam, St. George and Saint Andrews. Our inspectors can be reached by calling 466-7369.
This image shows one of the things our building inspectors are trained to spot. This pipe is a vent pipe – known to some as a “stink pipe,” in a renovation.
And it also created a violation of the National Building Code in the process.
Buildings these days are complicated things, and now more than ever, sub-contractors are faced with challenges about how to route things like water pipes, waste pipes, electrical wiring, communications and alarm wiring and the like through joists and walls.
Here’s the general rule on how to drill holes through studs or joists: Never drill a hole more than 1/4 of the thickness of the load-bearing member, and never drill a hole so that its edge is closer to 50 mm of the edge of that section of wood.
Load-bearing studs have more strict regulations, according to clause 220.127.116.11 of our inspector’s favourite bedtime storybook, the National Building Code of Canada, 2010 edition:
Wall studs shall not be notched, drilled or otherwise damaged so that the undamaged portion of the stud is less than two-thirds the depth of the stud if the stud is loadbearing or 40 mm if the stud is non-loadbearing, unless the weakened studs are suitably reinforced.
That’s what happened here: the pipe cuts through a load-bearing stud and is larger than 1/3 of the stud width. The hole was actually 2 1’2” wide, in a 5 1/2” wide 2x6 stud.
Fortunately, our inspectors aren’t just trained to find problems: they’re also able to – at least in situations like this – provide solutions. Our staff asked the framing contractor to install a 2x4 on the inside edge of the damaged stud from floor to ceiling to create a supplemental load-bearing element: but it could have been worse.
The big no-no: do not damage engineered trusses or open-web joists. If this is done, we will require the builder to obtain detailed repair instructions from the truss/joist manufacturer, which can cause delays in construction.
Here’s the entire “notching and framing” section of NBC 2010, for those inclined to study such things.
18.104.22.168. Holes Drilled in Framing Members
1) Holes drilled in roof, floor or ceiling framing members shall be not larger than
one-quarter the depth of the member and shall be located not less than 50 mm from the edges, unless the depth of the member is increased by the size of the hole.
22.214.171.124. Notching of Framing Members
1) Floor, roof and ceiling framing members are permitted to be notched provided
the notch is located on the top of the member within half the joist depth from the edge of bearing and is not deeper than one-third the joist depth, unless the depth of the
member is increased by the size of the notch.
126.96.36.199. Wall Studs
1) Wall studs shall not be notched, drilled or otherwise damaged so that the
undamaged portion of the stud is less than two-thirds the depth of the stud if the
stud is loadbearing or 40 mm if the stud is non-loadbearing, unless the weakened studs are suitably reinforced.
188.8.131.52. Top Plates
1) Top plates in walls shall not be notched, drilled or otherwise weakened to
reduce the undamaged width to less than 50 mm unless the weakened plates are suitably reinforced.
184.108.40.206. Roof Trusses
1) Roof truss members shall not be notched, drilled or otherwise weakened unless
such notching or drilling is allowed for in the design of the truss.