Render onto ICF

[deuce22]

Hi.

 

I have been told that you need to use a silicone render on ICF and had somebody give me a quote today.

 

He’s told me that He needs to scratch the surface of the polystyrene, use a bonding base coat called maite and push mesh into it, before giving it a second coat. Then he can give it one coat of parex. After that he sprays something else on top of it to stop mould and waterproof it.
He uses a pump to get the render on and the bags are different to normal, just over £30 compared with around £10. He's quoted me around £70 a metre. At that price, it would cost way to much. What have others used when using ICF?

 

Thanks.

[willbish]

I wanted to bring mine in at £50/m but its looking like nearer £70 now.

 

Currently undecided but leaning towards Wetherby 3.0mm K textured.

 

WBS-Thin-Coat-Systems.pdf

[nod]

42 minutes ago, deuce22 said:

Hi.

 

I have been told that you need to use a silicone render on ICF and had somebody give me a quote today.

 

He’s told me that He needs to scratch the surface of the polystyrene, use a bonding base coat called maite and push mesh into it, before giving it a second coat. Then he can give it one coat of parex. After that he sprays something else on top of it to stop mould and waterproof it.
He uses a pump to get the render on and the bags are different to normal, just over £30 compared with around £10. He's quoted me around £70 a metre. At that price, it would cost way to much. What have others used when using ICF?

 

Thanks.

Run a mile 

[nod]

We make plenty at £50 

As long as the scaffold is up 

[willbish]

24 minutes ago, nod said:

We make plenty at £50 

As long as the scaffold is up 

 

Cheers @nod ill keep looking then. Scaffold will be up and I can sort the garbage

[deuce22]

32 minutes ago, nod said:

We make plenty at £50 

As long as the scaffold is up 

 

What brand do you use? This plaster uses Parex, which is around £10 per bag, but said the bags for ICF is over 3x as much per bag.

[scottishjohn]

so thats another positive for woodcrete blocks --use anything  on it you would use on a brick wall

I did not realise that poly block need soemthing different 

[nod]

17 minutes ago, willbish said:

 

Cheers @nod ill keep looking then. Scaffold will be up and I can sort the garbage

Sorry to be a bit negative 

But as soon as you mention self build with many contractors They seem to think you have a big pot of money 

 

The only drawback with ICF and render is you really do need to leave the base coat for a couple of days In winter a week 

 

 

[willbish]

It was a big pot of money, not any more though!

[deuce22]

8 minutes ago, scottishjohn said:

so thats another positive for woodcrete blocks --use anything  on it you would use on a brick wall

I did not realise that poly block need soemthing different 

I've had a quote from Durisol, but it was double what I've had from Jackon.

 

8 minutes ago, nod said:

Sorry to be a bit negative 

But as soon as you mention self build with many contractors They seem to think you have a big pot of money 

 

The only drawback with ICF and render is you really do need to leave the base coat for a couple of days In winter a week 

 

 

I've noticed that, Some tradesmen act like I've won money with the prices they quote.

[nod]

43 minutes ago, deuce22 said:

 

What brand do you use? This plaster uses Parex, which is around £10 per bag, but said the bags for ICF is over 3x as much per bag.

I try to stick with Krend Acrylic if possible but have used Stucco and others 

Very often we don’t have a lot of choice in what we price for 

As I’ve said before the guys and girls that run K rend are second to none 

Slightest issue with the product and there over from Ireland for a site visit 

Once you have base coated and meshed the ICF you can use most through coloured renders 

ICF is less problematic than some of the high suction blocks 

If your plasterer is not a regular buyer in quantity of these renders 

Prices quoted can be high 

Not sure about three time’s though 

 

 

 

[Simon R]

50 sounds achievable (provided scaffolding is up). We came in below £50 m2 using JUB rendering system last June. The materials/labour cost were 40/60. The rendering company we used were recommended by JUB and did a first rate job (ejl.plastering@gmail.com). They were not fans of pump systems, preferring to mix and trowel. It's very weather dependant work and our job took three weeks elapse to complete. There was no "roughing up" of the ICF it's not required, well at least not using the products we used. It was also good to use materials from a single manufacturer.

[Archer]

We had a thin coat silicone render on polystyrene though and it looks great. They are about 7mm thickness when complete so it may be that the weight of other render systems is not appropriate for direct render to ICF/Poly? 

 

Used a system from EWI Pro and it sounds similar to what you've been quoted. The basecoat went onto jablite graphite eps boards which have some texture and there was no roughing up required. 

 

Other than that the method was identical to what you've been quoted except there was a primer applied between the 2nd base cost and the top coat silicone render and we didn't need a spray on top. 

 

Price for ours in London was about /£60m2 for a small extension job 25m2, but no spray pump needed. 

[deuce22]

Thanks Archer.

 

I've messaged the ICF companies to see what they advise. I'll have a look into what you had done, £60m2 in London is probably double of what it would cost in South Wales.

[nod]

£60 in London would be cheap

£30 even in s Wales wouldn’t be doable 

You would need most of that for your materials 

Unless you where going directly onto concrete block 

[Archer]

Agreed, we got a good price and the material cost for silicone render is significant. I was most impressed by the basecoat, it's a waterproof fibre reinforced cement product that you also use as an adhesive with external insulation. Pretty bullet proof stuff and looks good when finished. 

[Mr Punter]

I have had stuff rendered with just basecoat and mesh, rubbed up to a sanded finish and painted.  Used Weber LAC.  Excellent.

[deuce22]

Hi.

 

I've now got the plasterer doing the render on the garage. He is using Johnstones and has finished the mesh coat and base coat. I have gone out there today and noticed a lot of cracks. When you tap it, it feels really hollow and the cracks are moving when you press it.

 

Have any of you actually tapped it and does it feel hollow?

 

Thanks.

[Haylingbilly]

On 06/05/2020 at 08:04, Archer said:

We had a thin coat silicone render on polystyrene though and it looks great. They are about 7mm thickness when complete so it may be that the weight of other render systems is not appropriate for direct render to ICF/Poly? 

 

Used a system from EWI Pro and it sounds similar to what you've been quoted. The basecoat went onto jablite graphite eps boards which have some texture and there was no roughing up required. 

 

Other than that the method was identical to what you've been quoted except there was a primer applied between the 2nd base cost and the top coat silicone render and we didn't need a spray on top. 

 

Price for ours in London was about /£60m2 for a small extension job 25m2, but no spray pump needed. 

I used render from EWI Pro too - found them at one of the shows. They were great and 30-40% cheaper than krend