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4 Answers

Zip System R-Sheathing or Alternatives

Hi All
I recently purchased a 1977 home in Chicago Suburbs (Climate Zone 5) and looking at a 'quasi deep energy retrofit'

Exterior walls are 2x4 (fiberglass batts)
1st floor is cladded with brick
2nd floor has Stucco board with some kind of hardboard sheathing (and dry rotted tudor trim boards)

I'd like to resheath and reside 2nd floor for both asethics and energy savings.
Because of the depth of the exterior 1st floor brick in certain places I probably only have 1.5 inches of thickness from the outside of the 2x4 stud to the exterior face of the brick.

I was considering:

In Green building techniques | Asked By Tom Mitchell | Jul 12 16
10 Answers

Low temperature heat pumps

Ductless Minisplits are no longer the only answer to efficient heating in relatively cold climates!
There are, finally, air handlers that allow a fully ducted air to air heat pump system for small heat requirements in cold climates! Mitsubshi now offers the MVZ series, 12,000BTU/h,18,0000BTU/h,24,000BTU/h,30,000BTU/h,and 36,000BTU/h ducted air handlers that pair with their MXZ-C hyperheat outdoor units and together offer 80% + of rated heat output at -13degrees f.

In Energy efficiency and durability | Asked By Jerry Liebler | May 7 16
10 Answers

Insulating a raised floor over an old concrete slab

Hi, I have a house in Seattle. The back portion of the house has a 60 year old 600 square foot slab with approximately 2' deep footers. The ground slopes gently away from the foundation, and the roof overhangs each side by about 2-3'. Let's assume there is no gravel, sand, plastic, or insulation underneath the slab. There is no plastic or insulation on the exterior perimeter of the foundation either. The foundation perimeter vertically extends approximately 1/2"-1" above the slab. While the perimeter is level, the concrete slab is uneven, hence the 1/2"-1" inch variance.

In General questions | Asked By Jo Lee | Jul 8 16
6 Answers

Roof leak

I have had a slow leak in roof for about ten years and cannot fine the area of the leak.
The roof was installed over plywood in 1998 and consists of 30 year architectual shingles.

Around 2004 I noticed some water collecting in a light fixture. This only seems to occur when two conditions are present: Heavy rain and high winds

I naturally went into the attic and found water pooling on the sheetrock but even when up there during a windy rain storm on repeated occasions I have been unable to locate the leak.

In General questions | Asked By Rebecca Surprenant | Jul 7 16
4 Answers

Mitsubishi Heating Correction confusion

I am in the process of estimating the size of Mitsubishi FH series minisplits needed for a modular home in order to receive quotes from HVAC companies based on specific equipment requests and not their WAG assumptions. Will shortly be receiving a room by room Manual J heat loss calc.. The house will be located in zip code 12833 and so I am keenly interested in the minisplits ability to provide primary heating in an Upstate NY winter climate.

In Mechanicals | Asked By Doug Livingston | Jul 6 16
15 Answers

Who should fix this one?

My wife sent me a text today, as I am out of town, showing our garage door completely smashed in. We had a concrete contractor at the house today and at least two loads of rock brought in. The concrete guy said it was like that when he arrived, just after the first rock truck. The rock trucking company also has not claimed responsibility. Any thoughts on how I should resolve this? The rock was ordered by the concrete guy and not me for clarification.

In Project management | Asked By Mike M | May 21 16
4 Answers

T1-11 — overlay or replacement?

My 1979 T1-11 plywood sheathing has suffered what Martin has called similar to not drying faster than rate of being wetted. My intention is to overlay rather than replace simply because, if we can reduce the inrush of moisture and increase the drying potential, the labor of removing (organic) mass is not warranted. This is a (2) two story DOE #3 moist home. So--Here is my question-- Is there a concrete type (Hardie like) panel that lines up with the T1-11 reverse board and batten pattern, because I don't want to overlay /replace the upper panels that are appearing good?

In Green products and materials | Asked By Charles Thompson | Jul 11 16
6 Answers

Vapor barrier for a steel building used as a residence?

We're going to build an engineered steel building (44x70x12') for a residence. It will have four main steel supports on the long end, each a bit more than 1' deep. Purlins will sit inside the webbing, and are 8".

I wanted to put rigid foam on the exterior of the purlins, between the purlins and the exterior steel paneling. Unfortunately, the building company wouldn't validate that design.

In Green building techniques | Asked By Steve M | Jul 10 16
5 Answers

Replace bath exhaust fan details

20 year old builder poorly installed bath fan gave out so must be replaced. The fan is to the 2nd level master bath and the attic above is accessible unconditioned vented attic. I've read the GBA article on bath fans. http://www.greenbuildingadvisor.com/blogs/dept/musings/bathroom-exhaust-...

I've sized the fan properly. 400 cf room + 12' of duct with no elbows (I think; see below) + 30' to account for wall outlet = 60 cfm fan, per https://www.efi.org/factoids/bathroom_sizing.html. So I bought an 80 cfm fan. (Existing appears to be 40 cfm).

In Mechanicals | Asked By c l | Jul 4 16
7 Answers

Insulating a roof

Last year we moved into a log home in Tennessee (zone 4A) and have now been through one winter and a summer here. The home has a timber framed loft, which has proven to be difficult to cool in the summer and heat in the winter. The ceiling of the loft is 1" tongue & groove poplar, which also serves as the roof deck, on top of the poplar is ½" of blue board, then metal roofing. Using a DOE R-value calculator I get an R-value of about 2 - not good.

In Energy efficiency and durability | Asked By Steve Black | Jul 9 16
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