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1 Answer

Cape Cod Home - condensation on LL floors - mid-May through mid-September

Cape Cod Home - condensation on LL floors - mid may thru mid september... the basement is walk out with windows, slider, so a fair amount of air goes through.

I do understand the floor is colder than the air flow temp. The key piece of info is that there is no insulation under the concrete floor.

The real question.... can a layer of foam be put down over the concrete and then a sleeper floor over that ?? or simply the sleeper floor ? what is the correct way to mitigate that condensation problem on some level.

In GBA Pro help | Asked By PrestigeProperties | Apr 13 15
5 Answers

OSB for rainscreen furring?

Hey all - I'm going to be residing my single story house this summer (climate Marine 4c - Seattle). The walls look like this (inside to out):

Gypsum > 2x4 cavity (to be filled with dense-pack cellulose) > 1x8-1x10 shiplap sheathing > 15/30 lb Felt, taped > 1" polyiso > OSB furring (with core-a-vent sv-5) > hardie plank/cedar shingles.

In Energy efficiency and durability | Asked By Mateo K. | Mar 24 15
3 Answers

Diamond Pier usage

Is there any information available where 'Diamond Piers' have been used to support the construction of a driveway over bordering vegetative wetland areas ? I have to comply with a town conservation code that does not allow 'destruction ' of wetland to access buildable lots and it seems this system might work, but I cannot find that they have been used specifically for a driveway ??
Any ideas or help would be appreciated
GJAussie

In GBA Pro help | Asked By Garry Hopkins | Apr 10 15
97 Answers

Unvented slanted roof with radiant cooling and NO polyurethane in 4C

We are in Everett WA, north of Seattle, right on the coast, zone 4C. I hope that our location will save us...
We have a low sloping steel, west facing roof. Double, 30 weight felt paper underneath to dampen rain noise. I presume 1/2" plywood sheathing. 2x12" rafters, 11" true depth.
We will install WarmBoard R (13/16" thick OSB with aluminum tracks) underneath the rafters for summer cooling and supplemental heating in winter.

In GBA Pro help | Asked By Jan Verschuren | Mar 11 15
10 Answers

Best way to find the experts in my area

What or where is the best resource to find the top green architects/designers and builders in my area?

In GBA Pro help | Asked By Mary Dorcey-Mussog | Apr 1 15
3 Answers

What suggestions do people have to solve a R-38 roof problem?

We are building a single car garage over a studio apartment in the western North Carolina mountains, Zone 5A. The garage level will be accessed by an 18' bridge. The project is being engineered to address the structural issues of both the bridge and a second level slab to support the car. At this point it appears that we will be building the lower level with Logix ICFs of varying dimensions up to 12" and the second level slab will be supported by 10" Insul-Deck forms. The slab will be 4" thick.

In Building Code Questions | Asked By Jane Greene | Apr 9 15
17 Answers

Is this design OK for my vaulted ceiling?

I am new to this. I feel like I am back in college researching like crazy and finding too much info. This is the best site I have found. Keep up the good work. I have built several houses, but this one has a vaulted ceiling covering a 34 X 34 space. (This is my daughter-in-love's request. How could I say "no"!) However, I am beginning to have second thoughts. This is what I have come up with due to a variety of reasons.

In GBA Pro help | Asked By Tooger Smith | Apr 8 15
11 Answers

HPWH (in garage) in series with Electric Water Heater (in house)?

Hello,

I'm hoping to get a sanity check before proceeding with my water heater plan for a house I'm building, located in central Oregon (zone 5).

My plan is to install:

1) 50-gal Heat Pump Water Heater (GE 50-gallon model) in unconditioned garage space

> connected in series to downstream >

2) 50-gal Electric Water Heater (50-gal super insulated Marathon unit) in conditioned space in adjacent laundry room.

Some reasons this seems to be a good setup in my particular situation:

In Energy efficiency and durability | Asked By True South | Apr 8 15
0 Answers

Announcing a useful new feature on GBA

It's been a long time coming, but GBA finally has a "Recently Posted Comments" page. We've been wishing for this feature for years... and now it's here.

To get to the page, just click on the words "Recent Comments" that appear in the small box to the right of the Rotator images near the top of the GBA home page.

In General questions | Asked By Martin Holladay, GBA Advisor | Apr 10 15
3 Answers

Is what my contractor telling me correct?

I have placed a contract for repair and insulation of flat roofs. A fibreglass finish to the roof.
The contractor stated that screws to hold the Xltratherm boards in place would not affects the insulation values also that fibreglass insulation compressed into 75mm rafters by 50mm Xltratherm boards is equivalent to 140mm of Xltratherm boards.

Is this a reasonable statement?

I am trying to discover how much if any degrading in insulating properties occurs when insulation boards are attached to roof beams by screws.

In GBA Pro help | Asked By MikeDunwell | Apr 9 15
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