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11 Answers

Looking for design software recommendations

Hi -

I'm a new member and I'm looking for recommendations for relatively easy-to-use design software (I did try searching the site but didn't find anything discussing that). My first task will be a simple floor plan so I can ask the good folks here for advice on placing mini-splits. Further down the road, I'd like to be able to draw out details for roof and wall assemblies for the retrofits I hope to do. Any then maybe a tiny house (or at least a tiny shed) in the future.

In General questions | Asked By Nickolas Van Kleeck | Jul 23 16
1 Answer

Anyone have experience with Kohltech Supreme triple-pane windows?

I am considering Kohltech windows for my home build and am comparing them with tri pane Integitys. The have simmilar performance values but the Kohltechs are much cheaper. This is great, but also scares me a little since I have seen Integritys but not Kohltechs. Can anyone speak to their quality? Thanks for the help!

In General questions | Asked By Tim Burke | Aug 13 16
2 Answers

Cardboard insulation baffles have fallen down

Hi Pro Team!

I live in a solar (PV and HW), energy star house, built in 2005, in Washington, DC.

I was in the attic today and noticed that some of my cardboard insulation baffles had fallen over. I'd estimate about 1/3 of them. I don't go into the attic frequently, so they could have fallen over up to a few years ago.

Does this pose a problem?

Any guess on cause? Wind gusts blowing through the soffits knocking them over? Age (cardboard becoming less rigid)?

Thank you!

In GBA Pro help | Asked By Michael Harris | Aug 14 16
4 Answers

Fascia/soffit at held down gable

I'm trying to figure out how to frame the subfascia and soffit returns on a roof with the gable trusses held down 5.5". I don't want to do a wide fascia across the whole building, so right now I am planning a boxed return that steps up at the inside edges of the gable trusses, but I'm not completely sold on this solution. Does anyone have an explanation or images of how you have handled or would handle this detail? I am open to all suggestions. Thanks!

In GBA Pro help | Asked By Jim Tyler | Aug 12 16
1 Answer

Should I use this foam?

I recently got a bunch of polyiso foam pieces that I want to use on the outside of my house. The outside of the house has 4" of foil faced polyiso, but I have many attached porch roofs that have nothing between the rafters where they attach to the house. I was going to cut and cobble pieces in these spaces and can foam the edges. Here lies the issue, the foam I just got is 3" thick so I was going to double them up but I'm not sure about the facing. One side is a layer that looks like tarpaper and the other side looks like 1/2" of sound board, seems similar to suspended ceiling tile material.

In Green building techniques | Asked By darren williams | Aug 13 16
3 Answers

Can you use open-cell foam against OSB and provide a 3" air gap behind it?

Building a new construction home in a Mixed humid KY climate. Question is referring to insulating the attic space of a 4/12 pitch roof system with a standard roofline. Is it a good idea, logical or crazy to try to insulate the roofline of our 4/12 roof instead of the back of drywall ceiling deck. Plan is to form a 3" air shute from the vented eave between the 2ft on center rafter trusses all the way to the vented ridge using 7/16 osb or stapled in place insulwebbing fabric, applying 6" of open cell directly against the osb/insulwebbing fabric following the roofline.

In GBA Pro help | Asked By Cody Sturgill | Aug 12 16
0 Answers

Nudura Plus One & Plus Two

Anyone use the Nudura Plus One or Plus Two ICF systems?

The Plus one = R28
The Plus two = R32

Trying to get to PH levels on my build and it might require the Plus Two system. Looking at around $1,500 more in ICF forms with the Plus Two system vs the standard ICF forms.

In Green products and materials | Asked By Peter L | Aug 13 16
8 Answers

Is it better to combine an ERV with an air handler or ductless mini-splits?

We’re building a tight house (the Passive House metric of .6 ACH is the goal) with a significant amount of insulation (slab to attic R-values: 16-20-38-65) in the Chicago suburbs. Our house will be about 1,550 sq. ft. of finished space, single story, 2-BR, 2 bath, with a full basement.

I always assumed the HVAC system would be a basic combination of ERV and ductless mini-splits (for heat and AC), but our HVAC contractor is suggesting the following set-up:

Goodman air handler with 15K.W. Heat strips, for supplemental demand
Goodman 2 ½ ton Heat Pump 14.0 seer

In Green building techniques | Asked By Eric Whetzel | Aug 12 16
1 Answer

Rigid Foam on Flat Roof that Terminates to Mansard

I have a flat / Mansard roof. There is an addition to the back of the house that is the same roof type as the original two roof levels. The add-on roof is leaking. It has 3 leaking skylights that I plan to remove. The sheathing is very spongy. I plan to replace the sheathing and to use 3 layers of 2.5 inch polyiso rigid foam above the sheathing.
I only plan to work on the add-on roof for now. My plan is as follows:
1) remove / replace all old decking and any structural members that are rotten

In GBA Pro help | Asked By KALETA HILLIER | Aug 12 16
4 Answers

How to install fiber-cement siding over mineral wool?

I am planning to install 2" thick Rockboard 80 over Zip Sheathing using vertical furring strips screwed to the 24" OC studs. I am planning to install fiber cement siding on the outside of this assembly. I have two questions:

Are 1x4 furring strips thick enough to provide adequate material for the fiber cement fasteners to attach to?

In Green building techniques | Asked By Timothy Godshall | Aug 12 16
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