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7 Answers

Add R-14 Roxul between the garage attic and the house?

I am currently in the process of insulating my attached garage using Roxul R14 "ComfortBatts". I live in Winnipeg and from experience -- when I did this in my last house -- it can improve the temperature by 10-15 degrees Celsius in the winter, without any heating. (And that was with a non-insulated garage door; my new house has insulated garage doors!)

In Energy efficiency and durability | Asked By Mike Lucas | Oct 23 14
2 Answers

Basement slab retrofit questions

I have an older home built in the 1950’s. I’ve insulated the basement walls with rigid foam and a stud wall with batts. This has made the basement more comfortable, but I still have a lot of moisture in the air based on the dehumidifier that I run frequently. I’m fairly certain that the existing slab must be un-insulated and is missing any poly or other moisture barrier under it.

In Green building techniques | Asked By Mark Fredericks | Oct 27 14
4 Answers

Insulating detached garage attic in central Florida

I'm about to start construction of a 30' x 30' concrete block detached garage in central Florida. I'm using attic trusses and plan to use a white raised seam steel roof. I was not planning in insulate the block walls. What is the best way to insulate the roof? I want to keep it a cool as reasonably possible - I might add a window or portable AC, if I have to, but will not run it often. Depending on the final use of the attic, I might even try to condition that space. I'm concerned about moisture buildup inside - wet cars could bring a lot of water in.

In Energy efficiency and durability | Asked By Kelly Lear | Oct 3 14
2 Answers

How to deal with a void (cricket space) above an unvented flat roof?

Hi,
we're in the process of building a new house and originally had a non vented roof assembly detailed for the flat roof portion of the house where we had a single ply membrane over sloped rigid insulation over a vapor barrier over roof sheathing, with batt insulation placed tight against underside of roof sheathing.

In GBA Pro help | Asked By Rachel Kim | Oct 27 14
1 Answer

What's the best wall height for a ductless mini split heat pump?

Hello out there,

In Mechanicals | Asked By Theresa Spear | Oct 26 14
1 Answer

Is there a reliable way of repairing a double pane window if the seal has broken?

I have light gray spots appearing on the inside of the outer pane of a double pane sash window. They don't look like drops of moisture. More like translucent round snowflakes. Each round spot is made up of concentric rings. Frankly, they look beautiful.

I moved to this condo three years ago. The windows are about 7 years old.

In Energy efficiency and durability | Asked By stuart brodsky | Oct 26 14
3 Answers

What effect does home mass have on the peak cooling load?

Dr. Bailes presents a graph for his "old and leaky" condo in his blog "How to tell if your air conditioner is oversized". It demonstrates that his outside design temperature is reached at about noon. It also showed that the hourly run times for his a/c unit remain at lower levels until 5-8 hours later (notably peaking during hours 7 & 8). Presumably his "old & leaky" condo is not super insulated nor air tight.

In GBA Pro help | Asked By Ted Cummings | Oct 25 14
1 Answer

Spammers have Returned

It looks like those darn spammers have broken the "Math Code" Firewall
and or they have Learned Martin's Schedule.
.....
actually ....it looks like the "math test" has been removed.

In General questions | Asked By John Brooks | Oct 26 14
3 Answers

Oil filled heaters

I own a bungalow house with an apt downstairs. I have tenants upstairs and downstairs. Appx 600 square feet On each level. The house is heated by forced air oil furnace. The problem is the heat comes on everywhere Through house and can't be operated separately by the tenants. I've advised everyone to turn down Thermostat if you're out for awhile to let the other tenant "control the heat".
If someone leaves the heat on and the other tenant finds it to hot, they have to hit the kill switch to turn furnace off.

In Energy efficiency and durability | Asked By Tim Young | Oct 25 14
3 Answers

ERV, HRV, Dehumidifier retro fit before finishing basement

Hi all, I'm new here. Please bear with me with lots of questions.

I live in Zone 4A, with humid summer (100+ F, at least 3-4 months AC time), cold winter (-10 -- 0 F, at least 3-4 months heating), and wet spring and fall. Our house was built about 10 years ago. It has 3 HVAC systems for 4000 sq. ft. and additional 2000+ sq. ft. unfinished basement. Two HVAC systems are located in basement while the third one located in a closet on 2nd floor.

In Mechanicals | Asked By Wendy D | Oct 25 14
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