Wide cavity wall ties - what's available now?

gooner99

Bassalt Teplo wall ties have been recommended for a 200 cavity to reduce thermal bridging.

Are there now other alternatives on the market?

What have/are you guys using?

listermint

Any plastic wall tie will do.

Thats a large cavity, why so big

gooner99

listermint wrote: »

Any plastic wall tie will do.

Thats a large cavity, why so big

200+ is the norm now. I could be wrong, but I don't think plastic ties will suffice.

listermint

gooner99 wrote: »

200+ is the norm now. I could be wrong, but I don't think plastic ties will suffice.

Plastic ties would have no cold bridge.

Penn

listermint wrote: »

Plastic ties would have no cold bridge.

Cavities over 150mm require structural ties with specialist design. "Any plastic wall tie will do" is an erroneous comment to make as they may not be suitable structurally.

ht9zni1gs28crp

listermint wrote: »

Any plastic wall tie will do.

Thats a large cavity, why so big

This folks is the very reason you do not take structural advice off the internet

in fact the two sentences demonstrate the whole ideal of not taking advice off any forum.

Gumbo

listermint wrote: »

Any plastic wall tie will do.

Thats a large cavity, why so big

Please don't follow this advice.
Cavities above 150mm requires structural sign off by an Engineer to comply with Building Regulations at this width. Normal ties do not meet the requirements for structural codes or indeed the Building Regulations, Construction Product Regulations etc

Once the cavity exceeds 150mm, the 2 walls are determined to be acting independently of each other and cannot be classed as a twin leaf cavity wall under the EN/Structural codes.

gooner99

Thanks guys. Did some searching on the net. Seems steel ties are out due to the thermal bridging caused by the numbers required. That seems to leave Teplo bassalt and Qwik Fix glass fibre. Teplo seem to be widely used going by a search on here, where as there doesn't seem to be much use of Qwik Fix. Teplo I believe are more expensive. That seems to be the choice so far.

Gumbo

gooner99 wrote: »

Thanks guys. Did some searching on the net. Seems steel ties are out due to the thermal bridging caused by the numbers required. That seems to leave Teplo bassalt and Qwik Fix glass fibre. Teplo seem to be widely used going by a search on here, where as there doesn't seem to be much use of Qwik Fix. Teplo I believe are more expensive. That seems to be the choice so far.

Your engineer will confirm which ones comply
And which ones he/she is happy signing off on.

gooner99

kceire wrote: »

Your engineer will confirm which ones comply
And which ones he/she is happy signing off on.

Yes of course. Was just checking to see what else was currently on the market.

dfader

gooner99 wrote: »

Thanks guys. Did some searching on the net. Seems steel ties are out due to the thermal bridging caused by the numbers required. That seems to leave Teplo bassalt and Qwik Fix glass fibre. Teplo seem to be widely used going by a search on here, where as there doesn't seem to be much use of Qwik Fix. Teplo I believe are more expensive. That seems to be the choice so far.

Before you believe the sales pitches that steel wall ties create too much of a thermal bridge, get someone who knows how or look up the method on part l yourself to calculate the u value through the wall taking into account the fractional area of steel wall tie per meter squared of wall. Passive houses have been built with steel wall ties and pumped cavity.

ht9zni1gs28crp

The cold bridge by the stainless steel ties in our build wasn't deemed great enough to warrant the cost against the basalt ties. The cavity itself had enough in its build up to offset it. So dont rule them out just yet. From memory anything over 200mm the wall ties are installed at say 4 per m2 rather than the traditional 3 per m2.

Again your engineer will confirm these figures, not taking them off the interwebz :-)

Metric Tensor

kceire wrote: »

Once the cavity exceeds 150mm, the 2 walls are determined to be acting independently of each other and cannot be classed as a twin leaf cavity wall under the EN/Structural codes.

Not to be a nit picker .... As I go on to nit pick ...

That's not actually the case kceire. The Eurocodes will treat the wall as a double leaf wall even with wide cavities ... PROVIDED the engineer designs sufficient wall ties to ensure that both leafs act together. This is the reason the guidance documents say that once the cavity is above 150mm the wall has to be designed by an engineer.

adrianegan3

Anyone on here consider a 300 mm Cavity pumped as to get A1 u value and is the cost implications worth it

Penn

adrianegan3 wrote: »

Anyone on here consider a 300 mm Cavity pumped as to get A1 u value and is the cost implications worth it

You can get A1 rating without having to go to a 300mm cavity. The BER rating depends on far more than just how much insulation you have in your wall, and the cost of building with a 300mm cavity would be far better being spent elsewhere.

Gumbo

Metric Tensor wrote: »

Not to be a nit picker .... As I go on to nit pick ...

That's not actually the case kceire. The Eurocodes will treat the wall as a double leaf wall even with wide cavities ... PROVIDED the engineer designs sufficient wall ties to ensure that both leafs act together. This is the reason the guidance documents say that once the cavity is above 150mm the wall has to be designed by an engineer.

Maybe my wording of the post didn’t come across the way I thought about.
But my reasoning was that the wall can be considered as a twin Leaf with the engineers design and the correct wall ties.

I meant that just knocking up a wall with a 200 cavity and using standard ties, the wall can be be considered as acting separate if I am making any sense???

adrianegan3

Penn wrote: »

You can get A1 rating without having to go to a 300mm cavity. The BER rating depends on far more than just how much insulation you have in your wall, and the cost of building with a 300mm cavity would be far better being spent elsewhere.

Agree was considering putting in the insulated Raft system u value 0.10 so wanted to try keep walls to the same u value was considering the best route to get this . I am a blocklayer so laying of blocks isn’t big expense or putting in Cavity board vs pumped

Penn

adrianegan3 wrote: »

Agree was considering putting in the insulated Raft system u value 0.10 so wanted to try keep walls to the same u value was considering the best route to get this . I am a blocklayer so laying of blocks isn’t big expense or putting in Cavity board vs pumped

A Raft foundation would help lessen the cost of the wider cavity alright (as I was thinking about the wider rising wall & foundation that would be needed). Then again, such a wide cavity would require a lot of wall ties and at that width, could still be pretty expensive. I think a 200mm cavity would still have a low enough u value that spending the extra money in roof insulation, windows or heating system would be a wiser use of the money to get to an A1 rating.

An A1 rating really isn't all that difficult to achieve with standard enough details/materials so long as it's properly designed to take everything into consideration.

Gumbo

And making sure they are all used and fitted correctly on site is the hard job!

Metric Tensor

kceire wrote: »

I meant that just knocking up a wall with a 200 cavity and using standard ties, the wall can be be considered as acting separate if I am making any sense???

Even worse it might act as a halfway house between the two and lead to all sorts of unpredictable cracking!! :eek:

gooner99

kceire wrote: »

And making sure they are all used and fitted correctly on site is the hard job!

Are you talking about the wall ties. How can they be wrongly fitted?

gooner99

dfader wrote: »

Before you believe the sales pitches that steel wall ties create too much of a thermal bridge, get someone who knows how or look up the method on part l yourself to calculate the u value through the wall taking into account the fractional area of steel wall tie per meter squared of wall. Passive houses have been built with steel wall ties and pumped cavity.

Hi dfader. I take it you have wide cavity and steel ties. Can you pm me the details?

How is the building performing?

The_Bullman

gooner99 wrote: »

Are you talking about the wall ties. How can they be wrongly fitted?

Sloped inwards. Drip Upside down. Wrong spacings.

gooner99

Faye Itchy Cornflakes wrote: »

The cold bridge by the stainless steel ties in our build wasn't deemed great enough to warrant the cost against the basalt ties. The cavity itself had enough in its build up to offset it. So dont rule them out just yet. From memory anything over 200mm the wall ties are installed at say 4 per m2 rather than the traditional 3 per m2.

Again your engineer will confirm these figures, not taking them off the interwebz :-)

Hi Faye Itchy Cornflakes.

Is it a 200mm cavity you have?

Can you pm me the details of the ties?

How is the building performing?

ht9zni1gs28crp

gooner99 wrote: »

Hi miller_63.

Is it a 200mm cavity you have?

Can you pm me the details of the ties?

How is the building performing?

PM sent

ColemanY2K

I discovered a company in england called vista who produce basalt wall ties. thermal conductivity of 0.65W/mK which is slightly better than the teplo tp-2. best of all i found a supplier online in the uk (bs fixings) who sell them for £218.16 for a box of 100 (£2.18 each) + delivery. i can't seem to figure out what length these particular ties are. i fired off an email to get a quote.

has anyone used the vista wall ties? i'm looking for 375mm wall ties.

Metric Tensor

Get a professional to do a calculation for you to see how much extra heat you'll lose in a year if you just use steel wall ties.

For that width of cavity I'm guessing the benefits are miniscule when compared to the cost. And the minute amount of carbon difference will probably be offset by hauling them over from the UK!

kieran.

gooner99 wrote: »

Are you talking about the wall ties. How can they be wrongly fitted?

The_Bullman wrote: »

Sloped inwards. Drip Upside down. Wrong spacings.

Worst of all incorrect embedment. Very easily spotted in wide cavities and can be fixed with relative ease with remedial helical ties but it gets expensive if the brickie has been careless with their tie placements !!