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5 Answers

What roof underlayment can be used on a non-vented metal roof?

I've put up a building that has a 14/12 pitch non vented roof but now the building inspection dept. is hassling me over using Titanium UDL30 underlayment under the metal roof. They say it doesn't breathe and can rot the roof sheathing. The ceiling is R49 with 4" of foam against the plywood sheathing followed by 8" of fiberglass and 2 layers of 5/8" firesheild drywall.

I'd like to know 2 things - are my building officials wrong and if they're not what type of underlayment is allowable under a hot metal roof? I'm in the midwest in zone 6a.

In GBA Pro help | Asked By TeleTooler | Apr 11 15
3 Answers

Best subfloor for moisture and insulation under a basement rubber floor?

I would like to put a Roppe rubber floor down in my basement; it's soft and warm on the feet. I have an 80 yr. old concrete slab over which I'd like to add some moisture mitigation and insulation. The installation folks at Roppe suggest a 2 part epoxy paint on the concrete such as Mapei Planiseal, a portland cement for leveling, followed by the Roppe moisture resistant adhesive, and then the 1/8" rubber floor itself.

Reading the GBA site, I'd like to get 1" of XPS in there somewhere. The question is - where do I put it among all these layers?

In Energy efficiency and durability | Asked By Kate Wertime | Apr 11 15
2 Answers

Effectiveness of ductless minisplits for humidity control?

I live on the Texas Gulf Coast. We have to deal with heat and humidity. I live in a two story home not designed with ductwork. There is no easy way to use conventional HVAC. I am considering ductless mini-splits but I don't see how they remove humidity from the house. Please explain.

In General questions | Asked By Lanning | Apr 12 15
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

In GBA Pro help | Asked By Garry Hopkins | Apr 10 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)?


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
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