Ideas for insulating metal shed roof?

[beanybot]

Hi,

Basically just looking for some ideas here, all welcome!

I have a 10x13 Yardmaster shed which I have wired and set-up nicely as my little home workshop. Very happy with the shed itself.



I have a 3Kw fan heater in it which I can turn on and it heats it up pretty quickly but as you can imagine, being a puerly "tin" shed it looses its head very very quickly too.

Now I cant / don't need to insulate the side as these are mostly covered with tables, bookcases, drawers etc etc. But I would like to insulate the roof. I don't need it ultra insulated, just something that will "help". And most importantly, I need to do it as cheaply as possible as I have just had a big tax bill.

My initial thoughts were, get some polystyrene board and just cut it and spray adhesive it to the roof, maybe spray paint it silver to match. But I'm open to any suggestions. Do you think this would make quite a big difference to the heat retention? I would guess that most of the heat goes out the roof.

Thanks.

 

[AronSearle]

Polystyrene/rigid insulation onto roof, plywood, chipboard then felt....

Can't see why you can't do the same with walls, assuming the roof overhang would stop moisture getting in at the top.

Leaving the insulation bare or just painting it, meh, prone to damage and UV degradation. Moisture trapped between it and the metal could also promote corrosive action.

 

[beanybot]

Polystyrene/rigid insulation onto roof, plywood, chipboard then felt....

Can't see why you can't do the same with walls, assuming the roof overhang would stop moisture getting in at the top.

Leaving the insulation bare or just painting it, meh, prone to damage and UV degradation. Moisture trapped between it and the metal could also promote corrosive action.

Do i really need all those 4 stages? bearing in mind im trying to do it as cheaply as possible. Why felt?

Im just talking about insulating from the inside. sorry if I wasnt clear on that.
The walls are nearly all covered and fairly well insulated by objects anyway. And it would be a nightmare taking everything out again. Im just basically after something that will help. not trying to make it super insulated.

 

[AronSearle]

If doing it from the inside no, but you need to fully 'seal' with insulation.

If humid air gets in-between the insulation it can condense on the inside surface of the metal, this is why insulation tends to be sprayed or bonded to steel sip panels to avoid gaps.

'objects' and shelves provide no insulation, and you have more wall surfaces than roof, by all means insulation the roof, but don't be too suprised if the results are lacklustre.

 

[foxhole]

You can have cheap or effective, not both.

 

[beanybot]

You can have cheap or effective, not both.

Em, afraid I have to disagree there. Effective is simply a word that mean something that has an effect. Any insulation you use would "have an effect" i.e. be effective. Also, insulation is not on or off. it's an analogue scale. I don't expect 100% heat retention. That would be a bit tricky. So somewhere between what I have now and 100% would be good.

 

[freddiemercurystwin]

Waste of time just doing the roof.

 

[lbzbean]

What percentage of the outside surface area is the roof?

This is the maximum effect you hope to have even if you put in 100% effective insulation (such a thing doesn't exist).

20% ?

 

[AronSearle]

Effect, effective, blurgh, word play.

You have a giant metal box, you heat it = It is basically a big outdoor heater.

Stick some insulation on the top of your radiator and let us know how *effective* this is!

 

[beanybot]

What percentage of the outside surface area is the roof?

This is the maximum effect you hope to have even if you put in 100% effective insulation (such a thing doesn't exist).

20% ?

I dont think its a simple as what % is the roof. Surely because heat rises. the roof will loose more heat than say, a wall with the same surface area? I agree insulating the walls too would be ideal but they are already fully covered with stuff.
The thinking behind insulating the roof is that as heat rises, it will meet the insulation on the roof and be "reflected" back down. or indeed stay up there longer allowing a better build up of heat in the vertical column of air in the room.

 

[freddiemercurystwin]

it will meet the insulation on the roof and be "reflected" back down

and then straight out the sides!

 

[AronSearle]

heat rises.

NO IT DOESNT.

TEheeehehe

Honestly.....

 

[lbzbean]

I dont think its a simple as what % is the roof. Surely because heat rises. the roof will loose more heat than say, a wall with the same surface area? I agree insulating the walls too would be ideal but they are already fully covered with stuff.
The thinking behind insulating the roof is that as heat rises, it will meet the insulation on the roof and be "reflected" back down. or indeed stay up there longer allowing a better build up of heat in the vertical column of air in the room.

Sounds possible, intuitively I feel the difference would be fairly small, maybe multiple the area by 1.33 or something.

Put 25mm (or more) PIR board around all the surfaces and you'd be toasty.

 

[foxhole]

You can have cheap or effective, not both.

Em, afraid I have to disagree there. Effective is simply a word that mean something that has an effect. Any insulation you use would "have an effect" i.e. be effective. Also, insulation is not on or off. it's an analogue scale. I don't expect 100% heat retention. That would be a bit tricky. So somewhere between what I have now and 100% would be good.

Effective----successful in producing a desired or intended result.
Cheap option will not do that.

 

[mattylad]

Brick up around the outside, with a double wall & insulation between it, then make a good framed roof with slates on & insulation underneath.

Then remove the metal bits