Insul hub

[scottishjohn]

what the insul hub man +and durisol rep told me was to brace corners with 8x4 osb cut in half and then any other area that seems a bit weak 

only need for rebar in isotex is around door opening and window openings 

otherwise not need for uk --but fit if you like  no downside.

maybe if you live next the fracking fields .LOL

we are not earthquake prone like Italy and other parts of europe 

Edited April 18, 2019 by scottishjohn

[K78]

4 hours ago, scottishjohn said:

what the insul hub man +and durisol rep told me was to brace corners with 8x4 osb cut in half and then any other area that seems a bit weak 

only need for rebar in isotex is around door opening and window openings 

otherwise not need for uk --but fit if you like  no downside.

maybe if you live next the fracking fields .LOL

we are not earthquake prone like Italy and other parts of europe 

 

That is more reassuring. I was planning to brace the corners anyway. 

 

It didn’t make sense to me that durisol were saying 1.5m per pour. Dry stacking blocks is not rocket science. 

 

Looking forward to the isotex course next Friday. 

 

 

[scottishjohn]

2 minutes ago, K78 said:

It didn’t make sense to me that durisol were saying 1.5m per pour. Dry stacking blocks is not rocket science

well 

yes +no 

woodcrete blocks you use a much sloppier mix than poly blocks ,because they have more inherrent strength  and sloppy mix will not need to be poker vibrated to compact it 

It is the hydraulic weight that causes most blow outs ,so for foam blocks they use a thicker mix  ,but that needs vibrating  because its not as free flowing but too much compacting and that can actually burst blocks 

 then if you look at the velox panel system ,that too can use pretty sloppy mix ,again because the woodcrete is stronger and can let the excess  water in the concrete  mix leach into the pourous wood crete ,so setting it off quicker --poly blocks that water is going nowhere so mix will be more critical  

the secret is to not put too much  in one spot at once

so by the time you have walked round the walls --it has already started to set .

this is how you can build so high in "one pour"

It won,t actually be "one pour" cos bottom half should be firmed up before you get round again  . and then you will get a break waiting for next truck probably

polyblocks rely on the interlocking and woodcrete rely on physical weight  to keep them in place

I wonder why they don,t suggest using some sort of thinset adhesive between the blocks ,then this would not be a problem with woodcrete blocks no matter how high you filled as in 2 hours they would never come apart again

If you want belt+braces you could do that 

my guess its purely the cost ,which can be avoided with a  correct  pour strategy  and do a  slump test  for the concrete on each batch before pour  to make sure it is correct spec

 all these systems work if you understand the strengths +weakness of each system 

 

[K78]

Durisol confirmed via email today that they recommend stacking to 1.5m now. They say 2.5m is the absolute maximum. No clarification yet on why this has changed. 

 

I’m guessing a few people have had disasters at 2.5m?

 

 

 

 

 

[jack]

22 minutes ago, K78 said:

I’m guessing a few people have had disasters at 2.5m?

 

I assume part of the problem is not only the much higher risk of a burst, but the more severe consequences at that height. 2.5m means an awful lot of concrete to find its way out of a burst.

[ToughButterCup]

5 minutes ago, K78 said:

[...]

I’m guessing a few people have had disasters at 2.5m?

[...]

 

PMSL... wet the sofa, tea up my nose, cake stuck in my craw, coughing fit to cause a hernia.

Seen this?

 or this?

 

or read this? 

For a calmer take on things, read this ...

 

The height at which the wall collapsed was 4 meters plus.

You can  (but dont ever try it) pour a complete house. I have seen it done. Its a stupid (and should be ) an unnecessary risk. The pour height issue is one where willies are waved and sales spin weaved.....

 

I have a feeling that a good rule of thumb should be - dont pour more concrete than you are prepared to lose at any single pour. For me, thats about £500 (concrete, plus pump, plus reinstatement). Not all of the concrete poured will come out of any single block burst. Multiple block bursts will almost certainly be the result of negligent or criminal mishandling of the blocks or substandard blocks which should have been identified before placement.. Multiple block bursts are  rare, but in our case - a godsend. I kid you not

 

Read on

[K78]

Just now, jack said:

 

I assume part of the problem is not only the much higher risk of a burst, but the more severe consequences at that height. 2.5m means an awful lot of concrete to find its way out of a burst.

 

It will have a big say in which route I take. My whole plan and costing was geared around 2 pours.

 

Im glad one of the joiners I am using attended the durisol course with me. The additional concrete pump hire is costly and I would have people stood around on site doing nothing if we could only stack 3 blocks high. 

[K78]

2 minutes ago, AnonymousBosch said:

 

PMSL... wet the sofa, tea up my nose, cake stuck in my craw, coughing fit to cause a hernia.

Seen this?

 or this?

 

or read this? 

For a calmer take on things, read this ...

 

The height at which the wall collapsed was 4 meters plus.

You can  (but dont ever try it) pour a complete house. I have seen it done. Its a stupid (and should be ) an unnecessary risk. The pour height issue is one where willies are waved and sales spin weaved.....

 

I have a feeling that a good rule of thumb should be - dont pour more concrete than you are prepared to lose at any single pour. For me, thats about £500 (concrete, plus pump, plus reinstatement). Not all of the concrete poured will come out of any single block burst. Multiple block bursts will almost certainly be the result of negligent or criminal mishandling of the blocks or substandard blocks which should have been identified before placement.. Multiple block bursts are  rare, but in our case - a godsend. I kid you not

 

Read on

 

I was aware of your issues mate. But I thought they were down to the contractor not taking care with the blocks?

 

I was planning on going to 2.5m and pouring that day. 

[Russell griffiths]

Do a slump test.   

Oh yea what for??

 

please explain how you think that is going to work in your favour.  

It wont. 

 

Lets look at it. 

 

Your concrete plant is 35minutes drive away

your pump turns up at £600 for the day

you need 22m of concrete to do your first lift

first truck turns up and you do a slump test and all is good, so you pour in 7.5m, truck buggers off back to depot

second truck turns up 45mins later you do a slump test, oh dear it’s a bit wetter than it said in my spec, I know I will phone up and moan and send it back. 

So of goes the driver with his slightly too wet concrete, leaving you on the phone having a rant at the man in the batching plant (who couldn’t give a shit by the way)

the batching plant will tell you that they don’t have a spare truck available so you will need to wait for the mix to be tipped out and re mixed. 

The truck returns. 

This has taken the best part of a couple of hours, so it’s now 12.45 and you have got to get in 2 more truck loads, 

 

 

what I am getting at is if you set out your expectations so high something will fail leaving you in the poo. 

Learn to deal with what comes your way, brace the crap out of everything, then you can deal with with however the concrete is. 

Ask for it to come drier than your spec and adjust it on site. 

 

I have just put 39m of concrete in a nudura build, just 2 lifts up to 5.3m high. 

Didnt lose more than a bucket full. 

 

 

 

[Temp]

On 18/04/2019 at 21:58, K78 said:

 

It didn’t make sense to me that durisol were saying 1.5m per pour. Dry stacking blocks is not rocket science.

 

I've never used this type of system but I do a bit of physics on the side. The forces involved would make me nervous. The equation for the pressure at depth h is...

 

P= g*rho*h 

Where

g is 9.81m/s/s

rho is the density, which for concrete is 2400 kg/m^3

h is the depth

 

So the pressure at the bottom of a 1.5m high pour is..

 

=9.81*2400*1.5

=35,300 N/m^2

Or about 720 lbf per square foot.

 

Double the height and the pressure doubles.

[K78]

20 hours ago, Temp said:

 

I've never used this type of system but I do a bit of physics on the side. The forces involved would make me nervous. The equation for the pressure at depth h is...

 

P= g*rho*h 

Where

g is 9.81m/s/s

rho is the density, which for concrete is 2400 kg/m^3

h is the depth

 

So the pressure at the bottom of a 1.5m high pour is..

 

=9.81*2400*1.5

=35,300 N/m^2

Or about 720 lbf per square foot.

 

Double the height and the pressure doubles.

 

It will be interesting to see what insulhub say later this week. 

 

To be fair all the isotex YouTube videos say 1.5m per pour. 

 

Edit, The insulhub site says pour every 6 rows. https://insulhubuk.com/documents/8/ISOTEX_brochure_V4_2019_FINAL.pdf

 

Edited April 25, 2019 by K78

[Big Neil]

I had to cancel going tomorrow i'm afraid.I'm sure it will come up (of course if someone already knows the answer then post) but I'm be interested how they deal with hanging/seating joists. IN a polystyrene system it seems most sensible to me to hag a 'rim joist'?, like n the video in this link, but wasn't sure how they would go about this:

 

 

[Russell griffiths]

10 hours ago, Big Neil said:

I had to cancel going tomorrow i'm afraid.I'm sure it will come up (of course if someone already knows the answer then post) but I'm be interested how they deal with hanging/seating joists. IN a polystyrene system it seems most sensible to me to hag a 'rim joist'?, like n the video in this link, but wasn't sure how they would go about this:

 

 

That’s how I did mine, vey straight forward. 

[K78]

The insulhub course was good. The blocks are impressive and seem more uniform than durisol blocks. 

 

 

 

[Sue B]

I thought you would like them ?

[Big Neil]

What did they say about rim joists?

[K78]

As in your video. Really simple. 

[Big Neil]

ahhhhhhh - I hadn't imagined that. thought there might be another way with that system.

[ianfish]

This is part of our ISOTEX extension I have been working on, no real glitches. 

 

First time doing a build of this scale, its took me a year from groundworks til now.