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2 Answers

Insulating a non vented vaulted ceiling in Canada


I've recently had a 10x14 foot backyard studio built for me by a local company. I asked them not to insulate it because I was hoping to save some money by doing it myself. However, after some research I'm not really sure how to continue.

The studio has a vaulted 2x6 ceiling (with one skylight) with no ventilation. The soffits also have no vents. Initially, I was planning to just shove some fibreglass batts up there, putt up a vapor barrier and then finish it off with some wood paneling. However, after researching it sounds like that's a recipe for moisture and mold.

Asked By Kirsten Quist | Nov 28 15
3 Answers

SIP walls insulating the floor joists

I'm attaching a picture posted by Insulspan, the SIP manufacturer we're getting a quote from. It shows the SIP wall on the edge of the basement wall with the floor joists on the inside edge, providing continuous insulation of the rim joist. Has anyone seen this done? I thought at least 4 inches of the floor joist had to rest on the basement wall to be structurally sound. I plan on using superior walls which are 10.25 in thick and 8.25 in SIPs.

Asked By Brian W | Nov 28 15
1 Answer

To vent or not to vent?

First, I apologize for a question asked many times on here. After just asking about access to an unvented attic, I started to question the whole unvented idea. I live in zone 3, plan to use Zip R (R-6.6) with cellulose inside 2x6 walls.

I originally planned on unvented with 5 inch nailbase with around 3 inches of OC spray foam in the bottom of roof.

I've read every article I can find on the subject on here and other sites. If my ducts and air handler will not be in the attic, would it be better to go unvented? I know with unvented you gain a lot of volume of air to condition.

Asked By Eric | Nov 28 15
2 Answers

Locating manifold of a radiant floor heating system

Recently acquired a Condo that has propane fired radiant floor heating system. The house inspection showed it to be working. Recently as the cold weather begins in earnest the system cannot keep up... had a local reputable company diagnose the problem which they determined is caused by air in the system. They were able to remove some of the air at the boiler. As they drained water from the system it was very brown. In any case, the heating improved in some of the rooms as measured at the floor with an infrared thermometer. But not all. The thermostat was replaced with a programable model.

Asked By Carroll Ayer | Nov 28 15
14 Answers

Can PEX pipe be reused after a fitting is removed?

I've had 3 plastic on brass pex swivel connections fail. Each time I noticed water, reached up to check the connections only to have the nuts shatter in my hand. The first two times I used push connect fittings to replace the swivel fittings, connecting to the supply after the fitting was attached to the sink. After another failure yesterday on Thanksgiving I've decided to replace all the plastic on brass with all brass swivel fittings. I hack-sawed the pillow-top of the crimp connection then used a hair dryer to heat the pex, pulled out the brass shank and slid off the clamp.

Asked By K C | Nov 27 15
12 Answers

Two backdrafting appliances and dust — Do I need an HRV?

Hello, I have a problem with my house.

1) My house is probably air-tight

2) My water heater backdrafts whenever the bathroom fan is on. It's probably backdrafted every single morning (windows fog up & I feel the warm air at the flue when it kicks on....it only stops once turning off the bathroom fan).

3) Opening specific windows in the basement relieve the backdrafting of the water heater.

4) There was a lot of dust on a return-air duct that was right above the water heater. Another supply duct near the water heater had rust.

Asked By J Pritzen | Nov 26 15
1 Answer
4 Answers

How to create an air seal

We recently purchased a house that has a room with cathedral ceiling covered on the inside with cedar siding. This room, which was an addition has its own electric forced air furnace. Unfortunately, the builder of this room did not install a air barrier or even drywall under the siding, but did insulate the cavity above. This allows the thin cedar to leak at all of the joints. Blower door test and smoke confirmed the leakage.

I see two alternatives:

1. Remove the roof deck and apply spray foam from above, install a new deck and roof.

Asked By Dan | Nov 27 15
3 Answers

Humidity control other than plug in De/humidifier

Hi All,
I was wondering if there are any methods for controlling extreme humidity in the summer and extremely dry conditions in the winter that could be automatically implemented (other than just plugging in a humidifier or a dehumidifier).

I have a ground source heat pump in my 180 yr old stone house (uninsulated, because stone), and the humidity levels are extremely high in central Ontario in the summer (like, slippery floor level humidity) and extremely dry in the winter (furniture crackingly dry).

Asked By Terry Sharpe | Nov 27 15
4 Answers

Atypical cathedral insulation


I'm in climate zone 5A and trying to determine how to best insulate cathedral ceiling in farm/shop pole-type building with unusual design (picture attached). Building is multi-purpose with large portion un-insulated, but I would like to split loft section in half and use half for insulated workshop. Periodically heating around 60-65 deg at the most (but above freeze level all winter). Code does not apply for this building, but I don't want long term moisture issues.

Asked By Matt | Nov 25 15
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