We have installed four new dormers on our second level. It is now time for the insulation and we were wondering about spray foam insulation — does it get sprayed right on the inside of the roof or is there something there for venting? If there is nothing there for venting, will the shingles be affected after the insulation is sprayed? Thanks!
— Cheryl B., Ajax, Ont.
Well, Cheryl, this question really depends on how the roof is built. If you had the opportunity to put ridge vents in, then you can have some spray foamers come in, put baffles up against the underside of the sheeting and spray over top of them. That will allow for some airflow underneath.
You may run into a situation where the way things are built won’t allow for airflow. In that case, you’d typically have to spray directly onto the wood and eliminate an air cavity completely. It won’t necessarily kill the shingles. Most municipalities require putting some venting underneath the sheathing so moisture can escape. So, again, installing baffles would be the best way to go but in general, if there’s something like a flat roof that can’t be vented, then you’d just eliminate that airspace altogether.
I recommend you call your local building and planning department and see what their inspectors require in their area, because typically there’s some leeway depending on where you live.
Dear Bryan: We own a 1960s, ranch-style bungalow. We are thinking of painting the exterior brick next year. What preparation and type of paint should we use to get the best results? Thanks.
— Alan & Debbie Strang, Port Dover, Ont.
Good question! Brick is very porous — when you paint it, the paint actually gets into those pores, as well as in between the grains of sand in mortar, and into the brick itself. Deciding to paint brick is a one-way decision because, once you paint it, chances are you won’t be able to change your mind and go back to the original brick. You’ll want to think long and hard about this one.
Before you paint the brick, it’s got to be clean — it’s got to be power washed. Any ivy growing on it needs to be removed. Any issues, from cracked mortar to damaged brick, should be repaired first. Also, make sure the brick is dry. Since brick is so porous, you’re sealing all that moisture inside the brick when you paint it.
The next thing you’ll want to do is look for a good exterior primer. Talk to the people in the paint department at Lowe’s, as a source, about the options they have. Any good exterior primer and paint would adhere to the brick because it’s so porous. But there are a lot of options out there; there are even some exterior paints that don’t require a primer coat. Just make sure you’re sure about the colour you choose!
Hi, Bryan. We live in a cottage/house originally built on piers and open underneath. The floor was insulated with pink fiberglass insulation batts, without a vapour barrier. At some point, the basement was dug down, and enclosed with block walls and insulated. We have a furnace and a forced-air heating system not used all that much because we also have a wood-burning stove on the main. My question to you: Does the insulation under the floor serve any purpose and can we remove it completely? Best regards.
— Dave B., Haliburton County
Well, Dave, the vapour barrier is always on the warm side, so the floor itself and the subfloor act as the vapour barrier with the insulation underneath it. You wouldn’t have a vapour barrier on the bottom of the insulation if that area is open and unheated, as it was. But now that it’s been closed in and the exterior walls have been insulated, the insulation in the floor doesn’t serve any purpose. What you’ll want to do is insulate the joist bay, which is basically the area in between the joist that sits on top of the foundation. It’s a big area of heat loss.
So, in short: you can remove the insulation under the floor as long as the exterior floors are insulated properly and as long as that basement space is heated.
Bryan: We purchased a 70-year-old home four years ago. We loved the home and purchased despite the fact it did not have much insulation. It had been recently re-sided prior to the purchase. What would you suggest for both the walls and the attic?
— Debra and Andrew K., Grimsby, Ont.
Well, a 70-year-old home is right in that range where it may have been conventionally framed and may have had blown-in wool in the walls. But they’re also right around that age where they probably didn’t have an effective vapour barrier. The fact that it’s been re-sided tells me that it probably doesn’t make sense to rip all the siding off and do an EFIS (Exterior Foam Insulation System).
There are also methods where companies will come drill a hole in the drywall and inject foam. In my experience, that isn’t very effective because the wires and blocking in the wall can actually stop that insulation from really filling the wall cavity and adding enough R-value to make it worthwhile.
Really, my only suggestion would be to remove the drywall — or the plaster and lathe — on the inside, make sure you have enough space in the wall to bring it up to an R20, put a vapour barrier on top and put the drywall back up. Or you could open it up and spray it because that three inches of foam will give you the R20 you need in those walls.
So the answer is: there’s not a cheap, easy and quick fix. You may want to talk to an environmental contractor and have them do a heat-loss calculation on the home. They can use a thermal imaging camera to see if what you’re spending on heating warrants the cost of going in and re-insulating the house.
But in the attic, it’s simple. You can get in there, make sure there’s good airflow coming up through the soffits and you could blow in some more cellulose or chopped fiber material, tipping the R-value of the attic up. That will significantly save you some money because you lose a lot of heat through the attic.
Hi, Bryan. My sister had her bathroom painted and the paint is now peeling from the ceiling. She also lives in Maple. There is a window in the bathroom but no fan. Is it the paint or an air-circulation issue? Thanks.
— Carmela D., Maple, Ont.
Well, Carmela, there are a couple of things that could be going on. If it’s an older home, there’s a possibility that the original paint in the bathroom was oil and that it’s been painted over it with a latex. If that’s the case, the paint is definitely going to peel, whether there’s a fan or not. The second possibility is that maybe the ceiling wasn’t primed properly before it was painted, and that’s causing the issue. The third possibility is that you’ve got moisture coming from the attic; you’ll want to check up there and see is there’s any moisture coming down through the ceiling. The fourth possibility is that your shower is leaving a lot of moisture in that room, especially since there’s no fan. That moisture is going to rise and hit the ceiling and that will infiltrate the latex paint, making it could peel.
I would definitely recommend getting an electrician in to wire up a proper bathroom fan and put it on a timer, so when you’re finished showering, you can pop on that fan for 15-20 minutes and it’ll shut off on its own. There are a lot of possibilities about what could be happening there. But, no matter what, you should have a fan in there.