Durisol questions

[Tosh]

Hi all,

I'm looking for a some advice wrt our construction method. We're converting a steel portal frame building and have to keep the frame (cladding is to be removed and replaced with cedar up to 1st FL and zinc standing seam from 1st FL elevations and up over the roof). We intend to build the floor up from the existing concrete floor which is in excellent condition - this will still give us plenty of headroom as well.

 

 

We've set our sights on the Durisol block. I went on the course and liked the system especially the fact that it removed a lot of wet skilled trade and thus made it more self build friendly in the sense that I'm doing a huge proportion of it myself. However I do have some questions before we commit to it.

 

• If we chose the 365 block what would people recommend goes below DPC? Is it sensible to put these expensive, insulated blocks where their performance might not be exploited. Would it be more cost effective to use standard blocks up to DPC - I suppose the dimensions would be an issue though? That is getting blocks to marry-up to the 365 dimension? Have a look at the sketch up and pass on your thoughts please.

 

 

• We've been told by our SE to install vertical rebar on both gable ends. When this rebar goes through the DPC what do you seal the hole back with? Blackjack?

 

• We'd be installing the blocks between the steel stanchions. The detail is to use slip ties between the block ends and the steel to allow for thermal movement. Any ideas/comments on this? Any particular brand of ties and suitable infill around the stanchion?

• Overall do my learned colleagues think Durisol is necessarily the right system for this particular situation? I'm just interested to hear other peoples thoughts - I often think whether it would actually be more cost effective to build standard block and add external insulation though means getting mates in to do blockwork.

 

Thanks in advance.

 

Shaun

[Triassic]

Our Durosol expert will be along in a moment @recoveringacademic

[ToughButterCup]

Hi, @Tosh.

First, I'm not an expert. I'm a user. Hard bitten, and perhaps therefore a little less starry-eyed about the product. I am certain sure that there are some other products which will suit your needs, perhaps better. I assume you are converting an agricultural building to a dwelling - I may be wrong. 

 

 

DIY: perfectly possible 

But as soon as you talk to other trades, be aware of their possible resistance to anything new.  

' .... 'ow dja chase this stuff out 'ven ?  ... '

 

How are you going to cope with the possibility of bursts during a pour?  I am probably wrong in thinking that you might be tempted to keep the cladding in place and build up behind the cladding.

Have a strategy in place for coping with bursts during a pour. I can suggest a detailed way of coping - from very bitter experience.

 

Below DPC:  I can't help here.... sorry.

 

Slip Ties :  no experience I am afraid.

 

Is it the right system?   I don't know. But I do know you need to get your head round this issue to the extent that you know why you are NOT using other systems.  That might be as simple as a cost benefit analysis.

 

I would want to know what is under your floor - more precisely how much insulation is in place. The reason for the question is - why insulated well above ground, and (possibly) not so we'll under your feet?

 

Do feel free to PM me at anytime.

Ian

 

 

[Mr Punter]

I would not be keen in taking the cedar cladding so close to the ground.

 

I think it would be worth getting this priced in timber frame as it lends itself well to the type of proposed cladding.  You could still use the portal frame to support your roof which could be done in large cassettes.

[Onoff]

At least it shouldn't blow down...

[MikeSharp01]

6 hours ago, Tosh said:

If we chose the 365 block what would people recommend goes below DPC? Is it sensible to put these expensive, insulated blocks where their performance might not be exploited

Depends on how much insulating you want to do. If you have a solid base to work off and the BI is happy to have them below the DPC then you may get away with it BUT it looks complicated in that you have to fill those blocks, surface the tops of them then fit the dpc and find a way of connecting the upper and lower blocks to the  DPC - the tie in to the steels looks complex also. On the whole a timber frame with blown in insulation might be your best bet as @Mr Punter says.

[Tosh]

Thanks for the replies.

 

I got a quote for timber frame - it came in at around 75k. Yes it gave me the roof floor etc however they would not commit on how to detail around the steel frame until an order was placed. I could just see myself being hit with 'extras' or a load of assumptions in their price. Durisol comes in around 19k, say 4k for concrete, SIP estimate for the roof is 8K, say 5k for 1st floor joists, 4k for studding out.....Some of these aren't quoted but been priced for budget purposes by various suppliers. Yes there's all the other bits, vapour barriers, sealing, etc etc but still looks a country mile cheaper than TF.

 

We do also have the added complexity of having to put more steel into the frame which I think would hamper a timber frame more so than a block build. It isn't a straightforward job for sure whichever way we go hence anyone who comes to look either runs back down the valley (we're on top of the hills ) or takes a huge breath and moves the decimal point to the right!

 

@recoveringacademic I think you're spot on with asking oneself about why we've chosen this method. It's what's prompted me to write on this forum to hear others views. I've read your woes and believe me I've questioned myself on why Durisol however the cost/benefit over timber frame is simply too good to ignore, even with the agro with propping, etc. I do have a huge load of timber from the demolition of other buildings (the site was a former sawmills) which can be used for shuttering, props, dummy frames etc so that will help keep that side of costs down. I'll drop you a pm if you don't mind as keen to learn from your experience. BTW the cladding is being removed so walls will need to be propped in bays between the columns.

[Alexphd1]

Have you looked at EPS icf? 

[Tosh]

Not looked at EPS icf in detail to be fair. Dismissed it as I thought it would require a company doing thus more expensive than Durisol. Do you think it's worth enquiring about for this situation and if so any recommendations? We're not too bothered about speed of build, more value for money and quality.

[PeterW]

I would seriously consider building in 140mm block or even 2 courses of 100mm block inside the portal frame and then add a lot of EWI to the outside. It’s quick, relatively cheap and means you don’t need to worry about cold bridging from the floor into the steels. I would also be concerned about noise through the portal frame gaps as it will travel and that insulation type won’t help much. ICF is another good DIY option and then you could encase the frame in the ICF and make it a semi-warm frame. 

[Alexphd1]

Plenty on here including myself have used ICF On a diy basis. We are half way through parents build and will be using it again on my build hopefully starting in spring.

We used nudara icf and happy to use it again but will be pricing about, also had a good look at amvic icf and was also impressed. 

As PeterW mentioned don't rule out simple concrete block if using local trades sometimes pays to keep it simple.

[Russell griffiths]

Looking at those steels 

can you not use an ICF block or panel system and run both the inner and outer insulation past the columns and fully in case the steel within the centre of the block. 

 

any extra steels would be incorporated into the ICF by leaving out a beam pocket 

very diy able. 

I will be starting my ICF walls in a months time if you wanted a look. 

 

Where abouts are you. 

 

Im also using nudura 

it was not chosen by price, but by picking it up and getting a feel for how it will work for me. 

I would certainly get a couple of full blocks sent out to you, 

not silly offcuts proper full blocks so you can have a good play, cut some chunks off them, screw to them and anything else you fancy. 

[Russell griffiths]

we Are in Cirencester if you want to feel a few blocks

 

Edited August 29, 2018 by Russell griffiths
Cock up.

[Alexphd1]

Most icf suppliers do day courses. Money well spent even if it's the opposite and rules out ICF. 

 

[Tosh]

Thanks all - plenty for me to think about.

 

@PeterW I do like the sound of that. Though we would be losing 200mm of floor space around the perimeter - just got to get my head around giving that up

Very good point about the noise - hadn't thought of that.

 

@Alexphd1 good advice I think I'll take another look at nudura and amvic which I've not heard of before.

 

@Russell griffiths I'd be very up to visiting your site and having a look at the blocks you're using. I'm just on the Powys border, north of Hereford so only about hour and a half away. It's really interesting concept to encase the steels in concrete completely. I suppose I'm so used to seeing concrete dado walls between the walls in farm buildings that have cracked due to movement that I'm very (maybe overly) sensitive to that detail. PM me when would be a convenient time to come over.

 

Much appreciate all this help

[Sean003point5]

Speak to Durisol about a self build project very much like yours in Fairford. We went to visit it early last year and the owners were really friendly and helpful. It was a barn conversion where they had to keep the original steel structure and the Durisul system seemed to work really well for it.

Regarding your question about what to build below DPC, we built 2 courses of 365 mm Durisol but rather than use the insulated blocks we opted for the empty ones which are much cheaper. We then installed Jablite All In One (insulated) block and beam floor on top of those but with the added precaution of lining the non-insulated blocks with 100mm EPS.