How to insulate a sheet metal shed for sound and temperature regulation?

[Kitto]

Hi team, newbie on this forum.

I have read through multiple shed insulating threads on here and elsewhere already but cannot seem to find the best solution for my specific application.

The shed:

- Metal frame, metal sheet shed. Almost white sheets - quite heat reflective.

- Concrete floor - will likely have rubber mat put over the top.

- Located Adelaide Hills, SA - can be quite damp in winter.

- Use; Solar equipment and Generator room - significant heat and sound produced internally.

- Will be Air Conditioned, mainly for temperature regulation in Summer and humidity control in winter (pending available excess winter power).

- Ventilation and what type TBC

- Wall girts at 75mm thick, with fluted (superdeck) sheets externally.

- Ceiling insulation is half complete using foil backed glass insulation (space blanket) between the roof sheets and the purlins.

- In hindsight I should have fitted a vapour control barrier to between the wall sheets and the wall girts.

- All air gaps, holes etc are sealed up.

Goals;

- Moisture control - Probably the one aspect I am having the most trouble with solving how to control.

- Insulated for sound - keeping sound in (priority over temperature regulation).

- Insulated for temperature regulation.

- Shed will be internally sheeted - MDF / chipboard on the walls, gyprock ceiling.

Ideas that are not feasible:

- Removing wall sheets to add sarking / vapour control - two walls are sandwiched in place.

- Building an internal wall frame to support insulation. I only have the width of the wall girts to play with - 75mm plus a little more with the sheeting.

My current thoughts:

Ceiling - Add in a layer of acoustic insulation batt followed by gyprock. This however nets no air gap: Roof sheet > space blanket > acoustic glass insulation > gyprock. Noting the space blanket foil back glass insulation is designed to be in full contact with the roof sheet which it is. Alternatively install foil board or normal foam board that sits on top of the gyprock and provides some air gap to the space blanket insulation.

Walls - Initially I had intended to fit acoustic glass/wool insulation batts directly to the metal wall sheet, followed by vinyl mass liner then MDF sheeting. Reading into detail this doesn't seem smart as condensate could still form on the walls and cause mould on the insulation. Potentially I can cut vapour barrier to size and stick that to the wall sheet between each wall girt then place then fit the insulation. 

As stated above, my biggest concern is condensation forming notably in winter. Cold outside temperature with equipment inside producing heat = condensate. Any tips or advice would be great.

[Jason]

Welcome to the Bunnings Workshop community @Kitto. It's great to have you join us. 

I hope you found previous discussions somewhat helpful. This is certainly a popular topic and a common challenge. 

One of our resident Bunnings D.I.Y. experts will share their thoughts as soon as possible. In the meantime, let me tag a few other helpful members for their thoughts: @Dave-1, @JDE, @DIYgals, @haveago.

Jason

[Dave-1]

Good Morning @Kitto 

I have been following this company in the Big blue F social media arena and their product looks like it might be suitable for what you want. Weight wise may be an issue but as you are framing sections it could still work.

https://durrapanel.com/ Durrapanel looks like it can do more then just insulatre sound, not sure of the costings is all. I have seen rooms constructed with just the panels, no need for plaster so it could potentially do away with plastering?

For heat escaping I am thinking of some slatted styled vents that you can close off when you get to the cooler months Wall Vents maybe mixed in with a couple of wall exhaust fans Wall exhaust fans .

Dave

[EricL]

Hello @Kitto 

Your idea regarding the use of gyprock and foil board sounds promising. As long as there is an air gap between the foil board and the roof it should work nicely.

I'm aware that you're not keen on having a frame in front of your steel frame. Have you considered installing a slimmer timber frame using 70x35 and placing it inside the girt itself. You can put Ametalin insulation in front of the frame in combination with Permastop 55 x 1200mm x 20m R1.3 Light Duty Building Blanket. Although the gap will only be 5mm between the Ametalin and the steel wall, there will be at least a gap between them.

Let me call on our experienced member @Jewelleryrescue for their recommendation.

Just a friendly note to our New Zealand members the use of foil insulation products is prohibited

If you have any other questions we can help with, please let us know.

Eric

[Kitto]

Hi Dave,

Interesting product. After doing some very quick reading, it appears that it made and shipped to order and more suitable for large projects. I am ideally after an off the solution for acoustic and thermal insulation.

There will be forced ventilation when the generator is running. An inlet louvre damper and outlet damper with a suitable fan to provide fresh air to the engine and remove the heat generated. What I am still contemplating is if any static ventilation will be required.

[EricL]

Hi @Kitto 

If constant air movement is required, then it's best to install a solar ventilation fan or similar product.

Eric

[Kitto]

Hi Eric,

Thanks for the reply. Just to clarify your suggestion.. Working from outside to inside; Metal wall sheet > 5-10mm gap > Ametalin thermal liner fixed to timber frame > space blanket inside the frame with foil facing inwards > followed by wall sheeting (structural pine).

I like the suggestion, however it does add a reasonable amount of work and cost - not that I discount it immediately because of that. Another factor with this idea is I would struggle to get the frame in two sections of the wall where there is cross bracing fitted across the wall girts. There are also two locations where this plan would be unfeasible due to multiple conduits installed in the wall.

Thinking outside the box here.. Would taping sarking to the wall sheet be beneficial? I am not sure if this would be suitable or detrimental, but the way I look at it, if sarking was installed originally it would be sandwiched between the wall sheets and the wall girts and have full contact with the wall sheet. Taping it in place to the sheet will have a similar outcome except it would not be wedged under the wall girt. Then I could place foil board with a gap to the sarking > space blanket > wall sheet.

Regards,

[EricL]

Hello @Kitto 

It sounds like a good idea except that there is no documentation from Ametalin if it will work or not. I would have no way of giving you confirmation in regards to its effectivity. As you've mentioned earlier sarking is often placed on the outside frame first. I'll leave the decision up to you. 

If you need further assistance, please let us know.

Eric

[Dave-1]

Evening @Kitto 

As an outside the box thinking And I mean outside your shed lol

If you installed trellis on posts outside the shed, either bare or waiting for a vine to grow that would lower the sun heat effect dramatically. The other thing I have seen people do is a second roof over the top of the shed roof (usually a flat shed roof) with an air gap of about a foot. This would dramaticaly cool your shed as well.

Dave

[Kitto]

Hey Dave.

Whilst that is a good idea and I gave done this on my primary shed with solar panels, it isn't a suitable solution for my application.

My primary objective is keeping noise inside the shed - to an acceptable level with thermal insulation secondary - but still important. Both whilst ensuring moisture is controlled. All aspects need to be done within the shed walls.

Regards.