Composite wall-ties

soldsold

Anyone heard of/ used qwik-fix GRP wall ties?

I spoke to the company and they are about half the cost of UK teplo ties.

Independantly tested (no IAB cert)

Would I be mad to consider them?

I really dont want to use S/S wallties...

http://www.qwikfixings.com/wall-tie-specification.aspx

Carlow52

As u well know the issue is the use of non certified gear and then asking someone to sign off.

My opinion is don't do it

sinnerboy

+1

Graaaaa

I could see that getting and IBA cert could be a long process, if the only Irish Standard relating to wall ties is specifically titled "Metal Wall Ties for Masonry Walls", this is maybe why there's no indication that they're looking for certification.

As for independently tested, they have no claim on the website except that GRP has twice the tensile strength of steel. I have no opinion on this claim, I'll do some research into plastics later.

However I would be of the opinion that plastics have a much higher elasticity than steel - they will stretch more under tensile force, in this case from wind suction. The solution to this is to make the cross sectional area of the GRP ties much greater than for steel. From the image on their website this would seem to be the case. So far so good (pending testing or cert results).

Finally there is the subject of fire. I do not know how fire resistant or combustible GRP is, but certainly it is used for diesel tanks so it can't be that bad as plastics go. Steel looses it's tensile strength the hotter it gets, so the question is: under a fire load, particularly where the fire has spread into the cavity, which type of tie will allow the outer leaf to fall away first? Will it matter at this stage anyway?

The image of the tie has a few notches on the edge - the drip detail I guess? How does the insulation board get fixed tight to the wall? I don't see any clips shown. They would have been better off showing an image of the tie in-situ, like the Teplo Tie has.

Allowing for this being a new product and patent pending, and assuming my doubts above can be answered, then this gets the thumbs up from me.

sydthebeat

soldsold wrote: »

Anyone heard of/ used qwik-fix GRP wall ties?

I spoke to the company and they are about half the cost of UK teplo ties.

Independantly tested (no IAB cert)

Would I be mad to consider them?

I really dont want to use S/S wallties...

http://www.qwikfixings.com/wall-tie-specification.aspx

seems a very very convoluted way to solve a simple problem....

coat the steel wall ties in plastic and hey presto...


actually, its quite funny how they say that it 'improves buildings energy rating by eliminating thermal bridges'.... it doesnt eliminate the thermal bridge, it just reduces the thermal conductivity of the bridging material. Anyway, BR443 allows for wall tie bridging of less than 3% to be ignored.....

and as for allowing that shaped wall tie on a 300mm cavity (even a 200mm cavity!) i would be very very worried and would be looking for someone else to take the responsibility to sign off the structural integrity of the construction....

no cert = no use....

soldsold

Thanks for the replies (which were exactly as I anticipated )

Syd, you say to get plastic coated S/S ties. I assume this plastic coating is around the ends? Does it really make a difference? Plastic is not a very good insulator, albeit much better than steel.

As the ties are "coated" in Rockwool/ PU foam in the cavity when in normal use, does it make a difference to have a plastic coating?

I'm beginning to think I'll just use S/S steel ties and add a bit of insulation/ cavity width.

Or wear a light fleece top.


Steve

GenkiGenki

I'm building a house at the moment and contacted Qwik-Fix about their GFRP wall ties yesterday. Apparently they've just received certification to BS 845-1 as a type 2 wall tie, which means they can now be used anywhere in Ireland/UK in buildings below 15m in height.

The certification came from a company called CERAM in the UK. I checked them out and they're an accredited UKAS testing facility.

Regarding fire retardance, I'm pretty happy this isn't an issue. Glass fibres and the Isophthlaic Polyester resin they use in production both have excellent fire ratings. My engineer is happy enough to sign off on them, which suits me because those teplo ties are very expensive. I'm using a 200mm cavity by the way.

GenkiGenki

Sorry guys, a correction to what I wrote before; it's not a polyester resin the Qwik-Fix boys are using, it's a vinyl ester. Apologies for that.