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5 Answers

Exterior rigid foam options

Oh, building sciences... a week ago I didn't know you existed and now you make my head want to explode! Seriously though, thanks to all of you who have contributed to this amazing resource at GBA.

In Energy efficiency and durability | Asked By PA Marcotte | Oct 23 15
6 Answers

Rainscreen and exterior foam?

We meet with draftsman again today,we told him we would like to do 3/4or1 inch polyiso and also a rainscreen,he didn't know much about the rainscreen and wanted to know how we will handle windows and trim with the extra depth,I have mentioned before but this is not normal practice in Oklahoma(zone3) so we are kind of questioning is it worth it to put these behind our hardie lap siding or just do one and not the other?
Sence it's not normal practice I'm sure the builder will charge a lot more than would be charged in an area that it is normal practice.

In Energy efficiency and durability | Asked By Quinton Bryant | Oct 23 15
1 Answer

Would something like this be waterproof and vapourproof?

I want to put it on some wood that would have dirt up against the outside but be exposed to air on the inside.

In Energy efficiency and durability | Asked By Alan B | Oct 25 15
2 Answers

Strength of braces/brackets

My forty year-old house by a lake has 48" eaves (yes, 4 feet). There is a little sag at the corners, which are about 65 inches diagonally away from the corner of the house. The 48" overhang is covered by a flat section of roof that runs all the way around the house (hipped roof)-- creating something of a Japanese pagoda look. It was possible to walk all the way around the roof on a flat surface.

In GBA Pro help | Asked By Chan Joye | Oct 24 15
11 Answers

Alternatives to recessed lighting in open floor plans?

The question is basic....

For those of you who have forgone recessed lighting in your home for air sealing and efficiency reasons, what did you use for alternative lighting?

My floor plan is very open (think 20' x 40 box), has relatively low ceilings, 8'9", and I want the area to remain flexible for future floor plan changes. There is no kitchen area, just a very small snack island that will feature a few pendants.

For all their issues, can lights are a nice option for providing even lighting across an open area without having fixtures dangling down from the ceiling.

In Interior design | Asked By Rick Van Handel | Sep 3 14
20 Answers

Durable, yet breathable roofing underlayment.

I am building a home with a conditioned attic. I will be spraying 11-12 inches of open cell foam underneath the roof sheathing. I need to allow the sheathing to breathe to the exterior, for it will not breathe to the interior with the 12 inches of foam. Thus, I was wondering if anyone was aware of a roof underlayment (other than building paper) that is breathable, durable, and that has a high exposure rate.

In Energy efficiency and durability | Asked By JAMES MOYER | Jul 22 09
5 Answers

Recommended interior concrete stains & finishing?

I have a new construction small guest house with grey concrete slab floor and sawcuts in a 3 ft grid pattern. I'd like to stain it to look like mottled brown (leather look) and am wondering if anyone recommends a brand and method of staining and finishing that looks good, is durable, non-toxic, and low or no VOC. Just finished drywall texturing and ready to stain. Slab on grade (elevated 12-24" above finish grade) in Northern California, and slab edge is well insulated. also advice on grouting sawcuts (~3/4" deep). No cracking in 10 months since original pour.

Thanks for any advice

In General questions | Asked By Dan Burgoyne | Oct 23 15
8 Answers

What are your thoughts about a small kitchen without a range?

The kitchen in my condo is 82" x 69" so I planned to have a Wolf countertop oven instead of a range and a hood. The city building permit office approved the plan but a prospective buyer's lender insists the kitchen needs a range. Any experience with small kitchens without ranges?

In Building Code Questions | Asked By Mary Schwaba | Oct 22 15
8 Answers

Serious weatherizing of exterior doors

Gents ... I am surprised that I cannot find internet guidance on optimum door sealing design, tested methods and materials. I have a mid-range Lowe's back entrance door facing NW that allows some air in at the bottom corner all the time and when it's windy the air leak spreads up the jamb and across the threshold.

I have considered the following solutions:

- over-center compression latches - one at upper and one at lower ends of lock side of the door to push the door against the stops
- an aftermarket metal threshold jamb that pusheson the door base

In Energy efficiency and durability | Asked By Flitch Plate | Oct 20 15
7 Answers

Will open-cell spray foam require an additional vapor barrier?

I am planning to apply open cell foam to the interior ceiling and walls of my metal building. Currently, the building has metal siding with no vapor barrier and creates some condensation. The contractor is planning to apply the open cell foam directly to the metal siding. Will this be a problem? What will happen to the condensation? Will I need to add a vapor barrier?

In Green building techniques | Asked By Terry Blackwell | Oct 23 15
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