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4 Answers

How to seal 4" EPS foam at slab edge (radon concerns)?

Basement concrete 4" slab to be poured on top of 10mil poly, 4" EPS (2 layers staggered seams), and gravel at bottom with perimeter drains connected to vertical radon vent pipe. Building in a high radon zone, will the poly be sufficient covering the 4"x4" foam perimeter strips not covered by concrete at the slab edge? Should I be tapering the foam edge instead of keeping the full width of 4"x4" strips?

Asked By e c | Oct 29 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.

Asked By Rachel Kim | Oct 27 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.

Asked By Ted Cummings | Oct 25 14
4 Answers

Roof insulation

Home location in zone 2A Central Florida (Not on the coast). Having 2,053 SqFt living space w/above ceiling blown in insulation R-30 and an additional 1,027 uninsulated space. Fully vented at the soffet with minimal ridge vent. Soon to install 2 solar powered thermostat controlled 1600cfm roof vents. The wall construction is CMU block w/stucco finish. The roof is 6:12 pitch, Arch shingles over 30lb felt paper and OSB. The ceiling plane is tight.

Asked By Steven Clark | Oct 24 14
8 Answers

Attic insulation — existing

I have a 1800 sq. ft. ranch home built in 1969. Climate zone 5. Existing attic floor/ceiling area has a layer of 3" fiberglass insulation with vapor retarder facing the heated space. The second layer of insulation is a 3" layer of fiberglass with vapor retarder facing the attic area.

Both layers have been installed inside the joist bays and stuffed very tightly at the top of wall/ceiling intersection-no soffit vents in place. The roof has box vents and gable vents in place for ventilation.

Asked By bob prince | Oct 22 14
4 Answers

Insulation dew points and archaic insulation

I have a couple of questions, both somewhat academic since there may be little to do about them.

I live in a 1938 1.5 story (Cape-style) house in St. Paul, zone 6. About 3 years ago the shoddily-added back porch was falling apart and the roof shingles were shot , so I tackled both in one, replacing the back of the house with a new addition, and re-roofing the entire house using this "cold roof" article in JLC as a model (in short, adds 3" XPS foam plus 1-1/2" air gap above the original roof): http://www.jlconline.com/rooftop-accessories/retrofitting-an-insulated-c...

Asked By Graham Allan | Oct 20 14
2 Answers

Mold in crawlspace

I live in Gadsden Al,and we purchased a home and for a couple years its been smelling old,i went under the house and found the mold on the west wall where the flower planter is outside the house and by the pipes coming from the bathroom. I fogged the crawlspace very well with corcodium and I no I have to clean the walls too. But I need to bring the height of my front yard up 1 ft and at a slant to stop the water from ever going back under the house.the flower planter is 11/2 ft high and 12ft long 11/2 ft wide. and has brick on the outside.

Asked By weldon jones | Oct 21 14
5 Answers

Insulation design

Climate zone 2a.....south east Georgia coastal island. Bought a 1962 block one story house, The interior walls are painted block....we like the beach look associated with this concept. So, all insulation must be on the exterior of the house....which now us striped to bare block. Interested in the correct approach for water management and insulation. Exterior will eventually be cedar shingles.. Sort of thinking....spray closed cell between furring strips with ridged foam sheeting over the spray foam and strips. Then plywood covered with rain drainage screen topped with shingles.

Asked By Robert Brown | Oct 17 14
10 Answers

Radon

Question for you:
My basement was tested at 5.1 and then 6.5, short term tests. unoccupied space.
The living room first floor was at 2.7.

If still interested in radon mitigation, how can this be done at the slab if this is an 80yr old home that does not have any stone under the slab in the basement? The floor is on soil?

Thanks,

Dave

Asked By Dave Mac | Oct 13 14
9 Answers

How can I attach a ledger to an outside brick wall for a deck?

How can I attach a ledger to an outside brick wall for a deck when foam is used on the outside of sheathing?

I have 3 inches of foam then a 1 nice air gap, and I need advice on how to attach the ledger.

Asked By michael kasales | Oct 9 14
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