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4 Answers

I need assistance with window/door install with 4" foam

I am looking for some direction on installing windows and doors. I have 4" exterior EPS on a 2x6 walls

The current plan is to build 5/8" plywood boxes (I believe they are called Dewey boxes) to get the nail fin of the window to the same plane as the furring strips that the foam and the siding will be attached to.
I am sure its been covered but searching Dewey box got me 0 results so I wonder if someone could point me in the right direction?

Tim (Kenora ON Canada zone 7)

Asked By tim brown | Mar 28 15
12 Answers

Cool roof on a rigid foam retrofit


I have been doing extensive research prior to begining my remodel on my new home. I would like to get some advice on how to aproach my remodel.

The home is a 2600 sq ft contemporary style house. The majoroty of the roof is an unvented catherdral roof assembly. It is a simpole gable roof, although the North face is much steeper. It currently has an aging asphalt roof that will need replacing soon. I am planning a PV array instalation and need advice on what sort of assembly would be the best combination.

Asked By David Mosijchuk | Mar 23 15
3 Answers

Help with rainscreen options and cost for insulation on 1970s remodel

Hi, I am in Zone 4, Portland, Oregon.
My existing 1970's home is two stories with 2x6 framing with ) insulated walls(probaby still R13 in a daylight basement. Top floor main living room has 2x4 walls (R13). Existing Sheathing is Fiberboard sheathing (Cellulosic Fiber Insulating Board,).
I am tearing off existing combination of T111 and some other wood composite lap siding and installing a new rainscreen + fiber cement cladding, + new windows.

My Questions are:
1) What are the best cost effective option for a rainscreen layering if my fiberboard is intact and re-usable?

Asked By tauran ivall | Mar 24 15
2 Answers

Fiber cement siding over furring strips

In our region, which gets an average of 37" of rain annually, most folks put fiber cement siding against House wrap on OSB. Though there have been some projects we have seen that put the siding directly to the framing with no sheathing. In short order this is quite apparent because of the noticeable wave in the siding. We would like to start using furring strips on top of well sealed foam sheathing to create a drain pan. But we are afraid of the wave. We do quite a few resides and are typically dealing with 16" OC framing.

Asked By Hugh Stearns | Mar 24 15
5 Answers

What is the best way to manage moisture in a cinder block building in a hot, humid climate?

Having rebuilt my tiny bargeboard shotgun house in New Orleans, I now wish to turn my attention to the garage. Unlike the house itself, which has a pier foundation and a wood frame, the garage is a cinder block building on a concrete slab.

Asked By Shannon Holman | Mar 20 15
9 Answers

New PHIUS+ 2015 released and in effect as of March 16th, 2015

Interested to hear comments on the new PHIUS + 2015 that went into effect on March 16, 2015. They made a lot of changes and the biggest being the each climate zone and specific area will have its own standards. Not one big gigantic fits all approach like PassivHaus but very specific to climate zones, house size, etc.

Read more here:

Asked By Peter L | Mar 20 15
1 Answer

How do I integrate rainscreen at soffit?

I'm installing a rainscreen (1x4 battens) over 3" of polyiso foam and 3/8" plywood. I'm in Northern CA, zone 3B. My WRB will be Tyvek wrap over the foam. I understand how to terminate and vent the rainscreen at the bottom of my wall, but am not sure what this rainscreen should do at an arched soffit above my door opening.

Attached are a photo of the framed soffit above the door, before installing the rigid insulation. Also is a photo of this detail sketched out.

Asked By Dan Burgoyne | Mar 19 15
1 Answer

Attaching plastic attic baffles together

I purchased a bunch of ADO ProVent 14 inch plastic attic baffles.

I'm retro fitting them in between the insulation and roof in a cathedral type setup in a bungalow. So, I need to attach 2 or even 3 together before sliding them in.

I'm thinking of using Tyvek Housewrap 2inch tape, either on one side or both of the attic baffles to attach them to each other before sliding them in place.

I'm open to other products to attach them to each other. Any advice?

Asked By Jeremy M | Mar 19 15
13 Answers

Slag & fly ash geopolymer?

The father of geo polymers, Joseph Davidovits, has proposed a standard geo-polymer cement that uses fly ash, blast furnace slag and a "user friendly" alkali activator to make a cement. It' sets at room temperature in several hours and develops outstanding strength quickly.(7000+PSI @ 28 days). Without additional aggregates it is about 2.8/ inch. Since it uses about 90% waste materials it is quite "green". With that kind of insulating structural concrete far less plastic foam would be needed, a typical basement floor would be r10 by itself.

Asked By Jerry Liebler | Mar 16 15
1 Answer

Exterior foil-faced polyiso question

I live in the San Francisco Bay Area and my application is as follows:

Plywood – sealing all plywood seams with Signa Wigluv – 2 layers of ¾” foil faced polyiso (all seams taped) – WRB – Rainscreen – Fiber cement siding:

The plywood is serving as my primary air barrier. I understand that any moisture that gets behind the first layer of polyiso (between the ployiso and plywood ) will dry to the inside and any moisture that gets on the outer layer of polyiso will dry to the outside.

My question relates to the area between the two layers of foil faced polyiso.

Asked By Randy Mason | Mar 16 15
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