Drywall alternative
Just wondering, has anyone come across a wall board called Fermacell. I believe there is an importer in Quebec, but I have never seen it advertised here in Canada or in US.
It is a German product that I used in Europe for several years prior to coming here. Board for board it will be a much higher cost than drywall but if the total cost, including labour, less material, no drying time, is taken into account then it worked out much the same.
As a product I found it to be light years ahead of drywall. Very tough and durable,you will not punch a hole through it, no need to find studs to fix anything to the wall, good for sound, insulation and fire and it can get so wet as to have water running running out of it, as long as it can dry then it will be OK.
I am just curious as to why there would be no push to try it here, considering the amount of drywall used.
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Why won't it catch on? You answered your question.
"Board for board it will be a much higher cost than drywall"
It's just an 80% gypsum, 20% cellulose wallboard, made from recycled materials.
But if the other variants , labour etc, are taken into account then the overall cost is much closer. Believe me, having used it for several years it really is far, far ahead of drywall in just about every aspect. A much superior product that seems to address some of the common complaints I hear about drywall. I just thought that someone may have introduced it here earlier.
A Google search turned up two flavors of Fermacell - an exterior GFR cement board for sheathing and a cellulose-reinforced gypsum board for interior drywall applications. I assume it's the latter that Ray is interested in. The only way to reduce labor costs over standard gypsum drywall would be in the jointing, and yes when I had a look at the vid https://www.youtube.com/watch?v=Voi1B36yppg they seem to have a single-application joint compound which does not seem to need taping and or tapered edges on the boards. Other selling points would seem to be handy-dandy small-unit panels for small projects and limited access; better holding power for fixtures - 45 pounds from a single screw without blocking (or noggins, as the Brits have it); and altogether a rather more robust material than standard gypsum board. I don't know if this would be enough to allow it to break into the US market anytime soon - the jointing savings may well be less here as it's common practice in the UK to skim-coat the whole of the drywall in addition to the joint areas.
This video shows the framing and insulation prep for that same drywall job: https://www.youtube.com/watch?v=Ih42OKudR6g&feature=related. Curious to see what our resident experts think of a VB not on the outside, not on the inside, but sandwiched into the interior of the insulation layers.
By the way it's made by Xella, the parent company of Hebel. They've had very limited success with their AAC block in the US so I wouldn't hold my breath for a Fermacell release here anytime soon.
James,
The polyethylene vapor barrier doesn't cause problems in Britain for two reasons:
- Homes in Britain aren't air conditioned (yet), and
- British roofs are generally able to dry to the exterior because roofing often consists of slates or tiles installed on battens.
Placing the poly between two layers of insulation works -- at least in a heating climate -- as long as you have twice as much insulation R-value on the exterior side of the poly as on the interior side of the poly.
Ray,
Watching those videos, I'm not at all convinced that Fermacell is a significant improvement over standard gypsum drywall. And, since I use the Air-Tight Drywall Approach for air-sealing, I don't want to encourage fasteners in the walls except where there is framing behind.
James,
Canadians (and some intrepid Americans like me) have long used the 1/3-2/3 rule for vapor barriers (at least back when I was actually using poly). As long as the VB is within the inner third of the total R-value, it does not become a condensation plane, and it allows mechanicals to be on the warm side of the VB without penetration.
Robert, when I was building in England and Ireland I was using Fermacell without the insulation, just the boards alone. The wall make up was, from the inside, 12.5mm Fermacell, an air gap of 20mm created by strapping battens fixed to the studs, Intello+ 'breathable' vapour barrier (I think the equivalent here is Membrain by Certain Teed), and a double stud wall to an Rvalue of about 35. As the electrical boxes over there were only about 1" in depth they could be fixed within the air gap and so there were never any penetrations through the vapour barrier.
I designed and built my own home there with the above construction along with extreme air tightness, HRV, solar for hot water and some generation, a small wind turbine, triple glazed timber windows imported from Sweden. The house didn't actually have a central heating system as it sat between 14-18C all year round.
I much prefer living here in Canada though!!