Help with insulation

[theframer]

Hi All i should hopefully get the ok from the council soon to have a 17 feet X 18 feet 10" concrete sectional garge fitted to my garden for a framing workshop i am planning all the logistics for it and am looking into the insulation side of things,
I was thinking of 50mm celotex for the walls and ceiling and boarding over with 9mm mdf,my question is there will be a void of about 40mm between the wall and the celotex and was thinking of filling it with bubble wrap for a bit more insulation and sound prrofing do you think this would be ok? also looking at lighting i was looking at 5 x 6foot t5 double fluorescent's with daylight bulbs againg open to suggestions.
Thanks
Dave

[GeoSpectrum]

Can you fill it with more celotex? Think bubble wrap might be a bit of a fire hazard. I used 75mm of celotex when I insulated the extension to our house. Warm as toast. You might consider injected foam insulation as well.

[theframer]

Hi Alan
The void is not flat so cant add extra celotex as it will take up more space i was thinking of adding behind it to fill the void at a low cost as the celotex works out expensive i was going to use the loft insulation but the prices have gone up by a lot,

[misterdiy]

Actually I think the opposite. You should not try to fill the void since the void will allow any condensation to escape to ground. Ensure the bottom of the sectional shed is well painted with rust proofer. 40mm of Cellotex is good but I too would go for 75mm in one go. Plasterboard is cheaper than MDF and you can stick that with board adhesive too

[misterdiy]

Oh, and the lighting is spot on. We use these in the workshop. You will need to change the tubes every two years and probably replace the starters

[Merlin]

Will the Garage door be in use?
Will the Garage door be sealed. If not then I would not use Plasterboard or MDF. They both attract damp like a sponge.

I did exactly the same to my garage. I first lined the garage walls/floor and ceiling with sheet DPC.
I then used standard 'stud partition' timber between which I placed the 75mm celotex.
I then lined that with 8'x4' sheets of 18mm OSB. This allows you to fix anything to it securely.
On the floor, I used 25mmx25mm timber with 25mm celotex then OSB sheeting on top.
Belt and braces - I also run a dessicant dehumidifier.

It is worth spending the money now. I have my CMC, Morso, Underpinner, Excalibur 5000, PC plus 500 sheets of mountboard.

With all the bad weather we have had over the last 7 months. I am as snug as a bug. The dehumidifier only need emptying every 3 months so far.

[theframer]

Thanks for the replie's
The garage door will be in use i will insulate the door, i am going to fit a 50mm polystyrene into the concrete base and then i was going to use a concrete floor paint and then carpet tiles the height is a problem so dont want to use a wood flooring,
I was going to use timber studs on the wall for the celotex to fit inbetween,
I have a dehumidifier which i will run in there as well as a oil filled radiator.
Do you think i can still use mdf for the top boards,
Regards
Dave

[Merlin]

I was advised - by a number of builders and references on the web - NOT to use plasterboard or MDF but use OSB.

Even if you insulate the garage door, you will still end up with gaps around it. Wind and rain, will find a way in.

I certainly went with the 'belt and braces system' because of the expensive inventory inside.

[theframer]

Thanks merlin
I will go for osb board, how did you finnish the osb?
I want to do a good job just checking differant options that i have not thought of
dave

[Not your average framer]

OSB board is a low cost alternate to shuttering ply. It is rated for external use, while MDF, or plasterboard are only intended for internal use. OSB is nice and cheap! With a couple of coats of paint, it will look o.k.

What are you doing about the floor? It may get cold in the winter, even with the carpet tiles.

[prospero]

You might want to browse through my shed thread.

A concrete garage is a lot more substantial than a caravan, but you could use the same system of big frames made from 2x2. Roofing felt on one side and 19mm chipboard on the other. The void between is filled with slabs of insulation. It's like building a shed inside another.
Chipboard is great for workshop walls. You can fix shelves and stuff wherever you like.
I originally conceived this idea to beef up the structure of the caravan which was a bit wappy after I took out all the partitions. You would need to anchor the frames to the concrete outside in a few places, but the frames are quite rigid in their own right when you fix them all end-to-end.
For the floor I would lay roofing battens (they are pressure-treated) and fix 12mm chipboard to the top. Roofing battens are cheap if you buy a load so you can lay them close for rigidity. This would create an air gap which would serve as an insulator. You could also lay roofing felt under the floor to combat moisture rising from the ground.
With a bit of ingenuity you can eventually seal up any gaps where the wind comes in.

[Chris_h]

For my insulation I used Kingspan boards from Seconds&co on ebay. I paid about 150 for about 90 boards delivered. The condition was fantastic and I ended up using less than half the boards. I then stuck the other half back on eBay snd got £100 for them.

For heating i use a calor gas fire when im using the workshop which gives instant heat and quickly warms the room.

[Merlin]

I would not use Calor gas for heating where there is a lot of Mountboard around.

Check out the water content given off for calor heating.

[silvercleave]

The garage door??

If possible I would make the door smaller, when you lift the door you will loose ALL the heat. How about building a wall with a normal sized door in?

[GeoSpectrum]

I had a side hinge opening door fitted recently, cost £900 fitted but well worth it, a much better entrance for customers and deliveries and I don't loose all the heat in one big scoop of cold air.

[Chris_h]

I do have a dehumidifier going too with the Calor gas fire. This normally starts up as soon as I have the fire on and then stops any condensation forming as they do produce lots of moisture. But it does such a good job of heating the space up quickly it only needs to be on for five mins every hour or so. I started with an oil electric radiator but it just never got the space warm enoug and they are expensive to run constantly.

[theframer]

It will be a concrete floor with dpm and 2" polystyrene i dont want to add timber to the floor as height is very limited,
i will have a smaller personal door for every day use and just use the big garage door for biger deliveries,
I am going to batten the walls with 2 x 2 and then insulate between the battens,
I do have a dehumidifier and was going to run this with a oil filled radiator on a timmer,
I like the idea of celotex/kingspan as it will also give me a bit of sound proofing but as there is a gap behind the 2 x 2 battens was thinking of extra insulation on a budget.
Thanks
Dave

[prospero]

If you have room it would be great to knock up an enclosed porch around the small door.

[theframer]

No Room for the porch but will insulate it,

[prospero]

A conservatory is out of the question then?