Sheeting & Insulating Shed

Install building wrap against inside of existing top hat. Use the same top hat on the inside of the studs but at 600 centres. Fill gap between the top hats with bulk insulation. Sheet the inside with Colourbond in the Panelrib profile. (you could also use cool room panelling attached to inner face of existing top hat). Insulate the ceiling with foil backed bulk insulation sheet held in place with hinge joint or similar.

Hi amg989,

For an good result, run Insulbreak 65 (a kingspan Insulation product) along the inside of the shed battens taping the overlaps to seal the shed exterior walls off from the internal walls. Insulbreak 65 is a thermal break as well as an insulation. You can fasten it to the wall girts with wafer head tek screws.

Then using 22mm gyprock battens which are cheap! batten out at centres appropriate to you lining material, 600mm, 450mm, what ever you require. This will give a further air gap between the wall insulation and the Gyprock or Lining of choice. You can see some information on Insulbreak 65 here and see extensive tech specs at the manufacturers website here.

If lining a shed we suggest sealing the perimeter of the wall sheets with a vermin seal if there isn't one there already. A good vermin retroseal product is called Retroseal Superseal, you can read about it here . The idea being to prevent nasties from making a home inside your wall cavities.

Good luck with your project. I hope you get a good result.

The foil type insulations have their place, but that is not to be used as an alternative to bulk insulation especially when heat loss from inside a building to outside is a concern - such as in the OP's description of the problem to be solved. The Insulbreak will offer R values under R-2 Kingspan AIR-CELL Insulbreak® - R-Values while a bulk insulation of R-2.5 or R-3 would fit in that wall space. A new layer of the insulbreak under the roof leaving a gap between it and the foil already sitting directly under the roofing would work. Depending if you have plans for use of the walls I have lined steel sheds using 12mm construction ply or OSB which can be installed at 600 centres - vertically. For a steel shed best to simply by some new (or S/H steel framing or use more top hats vertically to bring the new wall face out to the steel support faces and screw the ply directly to it. Ply makes it easy to add shelves or hooks or otherwise add things to the wall and is easy mount and hard to damage. But Plaster board can be fine too and cheaper, but requires the joints to be done after fixing - plywood can say as is or can be coated with paint or whatever.

Have a read of the Insulation Manual in the Forum Library . . .

Originally Posted by Cuppa

Hi ‘Shedblog’,
Apologies for ‘grave digging’, but I plan to be similarly lining my shed in the near future & wondered if you might confirm whether I have understood your reply to amg989 correctly. Is my drawing below what you mean?


If this is what you mean, is any further addition required to ensure the thermal break continues in the spots where the batten screwed to the top hat (& compresses the Insulbreak), or is such a question overly ‘pernickety’ & not worth worrying about?

If lined internally with Gyprock would this arrangement give at least as good insulation as say an uninsulated conventional stud/single brick veneer wall in a house?

Hi Cuppa,

Your drawing looks fine.
The position shown of the Insulbreak will create the thermal break between your external steel wall sheeting and the Gyprock battens you desire.

Make sure you tape the overlaps of the insulation to create a good blanket seal trapping hot air away from the gyprock. If possible tuck the bottom edge of the insulation to the outer edge of the shed wall encouraging any condensation that forms (if by chance any does) to run to the outside of the building.

cheers, David

Originally Posted by Cuppa

Thanks David,
Do you have any thoughts on the suggestion that bulk insulation might be more effective? Using both insulbreak & bulk might be nice, but might become too expensive. As I understand it there would need to be some sort of waterproof layer between bulk isulation & the colorbond.

I am keen to create a living space (a ‘granny flat’ in one corner of the shed) which is warm & cosy in winter (which can get pretty chilly here).
The Colorbond walls in question are on the southern & western sides of the shed, & shaded by a tree on the western side too, so will not be in direct sunlight during summer much.

Hi Cuppa, One of the major benefits of the Insulbreak is the BREAK in thermal conductivity between the wall sheeting and the frame lowering the internal temp of the shed during summer and cold transferring via the frame in winter.

I'd do both if the budget allows.

cheers