ICF integrated Garage Threshold details

[magnethead]

Hi Guys,

I've ordered up all the insulation for my house floor, should be coming tomorrow, I meant to get these details sorted before now but I'm not really sure how the garage door threshold is going to work...I originally wasn't going to heat it, but now I've decided to give it a go with underfloor expanded from the rest of the house. The garage and the room above it are cut off air wise from the rest of the house, airtight line is between them and the rest of the house.

 

Anyway, Does anyone have any threshold details as, I now have to isolate the screed in the garage from the outside, you can see here my Door line comes down just inside the wall.

 

 

Thanks for any words of wisdom and even more thanks for any schematic details.

This is just to get the ball rolling, I'll knock up a CAD drawing later for this and put in any suggestions you make.

I scooped out 50mm concrete in the core before it set, and the plan was to cut the foam upstand bits off, and lay some kinda flagstone paving up to the door line.

 

 

 

[magnethead]

Here's a quick knock-up, The way I have it at the moment, there would be a cold bridge with the flagstones coming up to the Door sitting on the Concrete core (or maybe that is not something worry too much about? 

My main concern is the heated garage slab(With is thermally isolated from the rest of the house ground slab(120m2) having a cold bridge with the outside.

Anyone want to make a guess ? you could get to see your idea become a reality, as this all has to happen in the next two weeks, even though the screed lad is dragging his heels about getting over here to have a look.

 

The 'garage' will never have a car in it, It's more of a workshop

 

Garage_Threshold.pdf

Edited May 25, 2020 by magnethead
left out a small detail

[Vijay]

what about drainage?, surely you'll get water pooling in the 30mm channel?

Does this post help at all, at the end is an idea I've looked into https://forum.buildhub.org.uk/topic/2254-thermal-break-at-threshold/

 

Edited May 25, 2020 by Vijay

[magnethead]

Thanks @Vijay

Just read the whole thread. Yes, the channel would be a problem, but I don't plan to have the door open much, hardly ever. It would be better to have a gradual slope tapering off, something you could do with a tarmac finish, but I'm going for Stone just outside the building.

I take it you haven't pulled the trigger on your build yet?  I'm under serious pressure to come up with a detail fast We'll see how it turns out like...I'll report back here either way ?

[Vijay]

Mine is moving along but I'm way behind where I thought I'd be - but not stressing

[Russell griffiths]

I think we talked about this before, I seam to remember a fibreglass upstand to separate inside from outside, I think it’s what I’m going to do, you can drive over it but minimal cold bridge. 

[magnethead]

Thanks @Russell griffiths , Would you mind making out a little sketch of what you had in mind please?

 

I saw your comment at the end of @Vijay thread. Do you mean, you would put the Fibreglass angle under where the door would come down, and that would created a backing rod, to hold back the screed while it sets?  Vijay was talking about putting a galvanized T section in the middle of the core? But it's more then likely a door would be mounted on the inside face of the ICF and thus come down just inside the wall like in my photo above (correct me if I'm wrong Vijay)

[Vijay]

The T section could be anywhere in the core (or could be moved outside the core as long as supported with concrete I guess). The top flat plate could easily be bigger to bridge the space I guess, but how much it would cost I don't know............

[Russell griffiths]

I think I’m going to do something like this, I haven’t put a lot of thought into it but it’s sort of what I’m thinking. 

[Vijay]

Do you think fibreglass angle would be strong enough to drive over continuously?   What supports it?  Would be better than using steel!

[Russell griffiths]

1 minute ago, Vijay said:

Do you think fibreglass angle would be strong enough to drive over continuously?   What supports it?  Would be better than using steel!

I have got some XPS 500 I’m going to use that underneath it for support, it only sticks out 60-70 mm so not a lot, it’s very tough stuff

have a look at CHARLIE LUXTON  videos he sits his big windows on them. 

 

When you look look at the radius of a car wheel it will have very little contact. 

 

I did think of not having the angle at angle at all and just putting a polyurethane sealant on top of the xps. 

[scottishjohn]

11 minutes ago, Russell griffiths said:

I have got some XPS 500 I’m going to use that underneath it for support, it only sticks out 60-70 mm so not a lot, it’s very tough stuff

have a look at CHARLIE LUXTON  videos he sits his big windows on them. 

 

When you look look at the radius of a car wheel it will have very little contact. 

 

I did think of not having the angle at angle at all and just putting a polyurethane sealant on top of the xps. 

Iwoulld not be happy with a grp sill that has to withstand traffic --yes its strong but grp will wear very easily 

grp to water prooof it then maybe cover the bit that gets driven on with s/s or ally ?

Edited May 27, 2020 by scottishjohn

[Alexphd1]

@Russell griffiths Sorry to change subject but what's the xps500 coming in at m2 @ 100mm?

[Vijay]

26 minutes ago, Russell griffiths said:

I have got some XPS 500 I’m going to use that underneath it for support, it only sticks out 60-70 mm so not a lot, it’s very tough stuff

have a look at CHARLIE LUXTON  videos he sits his big windows on them. 

 

When you look look at the radius of a car wheel it will have very little contact. 

 

I did think of not having the angle at angle at all and just putting a polyurethane sealant on top of the xps. 

 

I remember us chatting about that video and we were talking about your idea on doors. My concern with car traffic is what do you do if/when the GRP is damaged - how easy to fix the situation

[AliG]

Everyone is being very helpful re the details here, but before going any further can I make a few points.

 

1. Garage doors provide a pathetic level of insulation and air tightness. If you take a picture of one with an IR camera, much as the centre of each panel is insulated, the edges are not. Nor is the frame etc. The amount of heat you lose through a cold bridge at the edge of your slab will be inconsequential to what you lose through the door and the door frame.

 

2. I thought at one point that this was a good idea, but my research suggested that heating your garage and putting a damp car in there is bad for it. If you plan to use it as a heated workshop that is different, but if you plan to put the car in there it is a bad idea.

 

3. How much time do you actually spending the garage? My unheated integral garage with a 40mm insulated door drops to around 10C when it is cold outside. This is much better than keeping a car outside and fine to nip in there to put the trash in the bin. So again unless you plan to use it as a workshop and spend hours in there it would be a lot to spend for not a lot of use. Of course if you want to it is up to you, I have been thinking of plastering and tiling mine as it would look nice but then I keep telling myself I don't really need to. So far sense is winning.

 

[scottishjohn]

if you heat it to dry a wet car ,then you need ot ventilate it to get rid of the moisture

MVHR sounds like something a footballer has for his mc claren 

[Russell griffiths]

43 minutes ago, Alexphd1 said:

@Russell griffiths Sorry to change subject but what's the xps500 coming in at m2 @ 100mm?

Not really sure what it cost, I just bought one pack of 80mm for under my door threshold. 

Its kingspan greengaurd. 

[Alexphd1]

I didnt know such material exsisted!

[Russell griffiths]

Just now, Alexphd1 said:

I didnt know such material exsisted!

Small size sheets 1200x 450 maybe, cannot remember, with a rebate edge all around so they lock together, sort of. 

You can stick it through the table saw with a bit of melting and dust. 

[magnethead]

HI Guys,

Thanks so much for your replies, It's my first time building and I don't have much exposure to this industry apart from  a few summer jobs onsite. I got a lot of Solace from @AliG post, that's a very practical/experienced look at things and it's helped me get a bit of sleep on this. I had a close look at the door, and even in the joints between the panels, you can see gaps to the outside where you would nearly put your finger through.

 

 

 

This garage will only be used as a workshop for me, so without thinking I ordered up all the insulation for the house, It's Kore100 insulation. I was told by the screed company, I would need higher density stuff for the garage if I ever wanted a car in there(I won't but if I sold the house, the new owner might, so I've asked them to exchange that bit of insulation) which is delaying things a bit, not a bad thing as I still need to sort out this threshold.

 

So leaving aside Thermal issues for now, I see I have a massive NEW problem as I measure the door, and the front surface is actually recessed back 40mm from the insulation ICF insulation  I'm going to need some kind of tray to carry water out side, I wasn't planning on putting an ACO drain outside the garage but maybe I need too.

 

Here is the threshold at the moment.  I am an amateur welder, so something made up out of stainless steel would be an easy option for me.

 

 

 

@Russell griffiths  I checked out a company selling fibreglass angle here 

https://glassfibre.ie/product-category/roofing-trims/

They seem to have only 75mm x 75m angle.......... THen I got onto a guy who makes surfboards, who said he could make up something custom, might need to make up a aluminium shutter first to make the piece.

I was hoping to leave a little trough for the bottom of the garage door to go into, you have an almost flush design which makes better sense if the garage is being used for a car to drive in and out of

 

I'm going to need some kind of tray(see large area outined in red at the bottom of the attached dsrawing) to carry the water away from the underside of the door and under the stone slab...I have plenty of Fibran insulation left over, I was using that under the screed where the stairs lands. so I stuck it in the gap in the updated drawing 

 

Thanks for any advice you can provide

 

 

 

 

 

 

Garage_Threshold1.pdf

Edited June 6, 2020 by magnethead

[AliG]

One thing to watch is that driven rain runs down the door and easily gets underneath it, in our last house, they didn't put a run on the area under the door so water ran under the door and into the garage.

 

I don't think the door closing into a slot is a good idea as it would fill up with water.

 

Looking at your picture, why not run the flagstone just under the door above the Fibran, putting a slight run on it so the water runs away from the door. Then cut a 20mm wide channel in the screed behind the door (or put an edge there when you screed the floor) this way the flagstone will not touch the screed. As the channel is inside, it wouldn't need covered, you can just drive over it. You might want to cover it to avoid it filling up with dirt or rain when the door is open however.

 

 

Garage_Threshold1.pdf

[magnethead]

Just finished laying all my insulation in the rest of the house apart from the Garage.

Thanks very much @AliG  I love your Idea of bringing the flag stones under the Door, That Look like a Runner. I'll use a Good DPC under them to carry water to the outside and it should be Good.