Thread: Shed lining sanity check

This issue has been near flogged to death in various Shed Threads.

Rather than hearing the same waffle and counter arguments all over again how about we address your specific, "things I have read recently have given me cause to think again"

Originally Posted by BobL

how about we address your specific, "things I have read recently have given me cause to think again"

Sure! I may not have written the original post too clearly, and my apologies if so. Also, thank you for the suggestion of other threads, I had looked at the last couple of years worth, but thread titles only, and have obviously missed much good information - I'll be going back and reading in detail!

Here are the specific issues I am concerned about:

Originally Posted by Midnight Man

In particular I'd like to know if sealing that gap with a foam (or other material) will lead to a condensation problem?

Will any walls/insulation being constructed need to allow an air gap between them and the existing lining and colourbond wall to prevent condensation problems?

My thinking (though I was keen to hear alternative suggestions) was for the wall construction to be H2 treated pine frame (90x35) built in between the 150mm structural beams (i.e. it will sit in between these, and be anchored to them).

Between this frame and the concrete slab I was going to use a flashing to prevent the H2 pine from coming into contact with the concrete (I should note the concrete slab does have a vapour barrier built in, so I'm not sure if this is really required, but it's not hard or expensive to do this).

On the back (outside) side of this frame, I was planning on using 5mm Hardie Brace on the basis that it wasn't timber, wouldn't rot, and would provide racking support and support for insulation in the cavity. Hardie Brace here: HardieBrace™ sheet | Technical | James Hardie

Behind that I was going to use something like a Tyvek wall wrap for a moisture barrier.

Of the front (inside) of this wall structure I was going to put in 19mm yellowtongue flooring for wall strength against bumps and dings, and perhaps then face that with a nice looking 3mm ply (perhaps a bit thicker, as any additional wall material would add to noise insulation I'd imagine).

My thinking was that this entire structure up to but not including the ply would sit in the space between the structural supports, and come level to the inside edge of them. Over the top of the whole thing I would put the ply lining.

All of this, by my calculations, including a 1mm allowance for the Tyvek, comes to a thickness of 115mm (excluding the plywood), leaving a gap behind of 35mm plus an additional 60mm left by the horizontal beams in the structure.

This would, I imagine, allow plenty of air gap to deal with condensation were any to arise - however, this space could be used to install additional acoustic insulation.

It is from the desire to install additional acoustic insulation that my concerns stem from - if I were to seal the bottom edge of the colourbond to the concrete (see original post) and/or use the gap I note above for additional acoustic insulation (potentially pushing it up against the Insulshed lining), am I going to find a condensation issue (and thus, possibly mould) building up inside this wall structure?

A build up of Condensation should only occur under circumstances whereby excess amounts of moist air can enter wall and ceiling cavities.

If a large amount of moist air can enter a cavity and there is a cold surface inside that cavity (like the underside of sheet metal at night) then this can cause moisture to condense out of that moist air. However, I note you already have insulated the sheet metal on the inside with Insulshed so condensation should already be minimal in the wall cavity and means you can pretty well do what you like in between the Insulshed and any shed lining.

If you didn't use Insulshed then a simple sealed cavity that prevents moist air from easily entering the cavity would be an alternative but this would then allow more heat to get into the shed.

An alternative to sealing the cavity is to fill the cavity with some sort of space filing material eg insulation like rock wool or other filler.

If you want to minimise noise transfer you could do some of the following ;

A) Fill the wall cavity with some sort of softer acoustic absorber and then use a thinner shed lining that is thick enough to support your gear. This will allow some noise to escape through the thin shed lining but the acoustic insulation should absorb most of this. There are material around that can act as both some sort of acoustic and thermal insulation to gain extra thermal protection.

OR

B) Seeing as you have already used Insulshed just use a denser thicker material like MDF or ply, and nothing in the gap as the dense thick material will tend to reflect noise generated inside the shed back into the shed as well as providing a substantial surface to hang things on. Noise wise this is not quite as good for a user inside the shed but should be just as effective as far as reducing the noise getting to the neighbours. This is what we did at the mens shed.

To deliberately reduce noise inside a shed shed requires either (1) exposed thick/soft surfaces that absorb the noise or (2) irregular surfaces that scatter noise in multiple directions. The first method is not that compatible with workshops (fire hazards etc) while the second method is invariably what happens in most DIY wood working sheds as they are small and cluttered and turn into a bit of a mess so there's usually no need to deliberately introduce scattering systems. If you had a very large barn like structure lined with a hard dense material it could sound very echoey and loud. Imagine a full size thicknesser running inside a stone walled church.

OR
C) You could go full belt and braces and use some a combo of A and B. Reversing the order of soft/hard would be better for users inside the shed. So, starting from the outside the shed; Sheet metal outer skin, Insulshed, Thick/dense material and finally soft acoustic absorber, but then you wouldn't have your firm surface to hang things off so a thin rigid shell over the top of the acoustic absorber would fix that. If the cavity is completely filled or sealed there is less of a need for the insulshed although that will help significantly with thermal insulation.

Clear as mud?

Originally Posted by BobL

Clear as mud?

Clearer than that, and thank you - it seems my concerns on the condensation side are unfounded

Sincerely appreciate the advice, I shall plod on with the build!

Originally Posted by Midnight Man

Clearer than that, and thank you - it seems my concerns on the condensation side are unfounded

Glad it could be of help - check my signature

Originally Posted by BobL

Glad it could be of help - check my signature

Heh - something is wonky with my browser, never saw it before (loaded this thread in another browser to see it)

MDF is cheap, sturdy, stable & easy to paint. Anything over 10mm does a good job soundproofing however 19mm is really good.

I had a small nightclub and was getting noise complaints. 19mm mdf across the entry way fixed it totally. Even the EPA was happy.

I lined mine in similar fashion used vertical Tophat 64 battens at 600c/c screw fixed to the horizontal beams, which are known as 'girts'. My install wasn't quite as straightforward as I retrofitted Thermalbreak 8 foil insulation on the inside of the purlins and girts (yours is on the outside, as it should be) but it worked out fine. I shimmed the battens up off the floor slightly to avoid any moisture issues down the track.

The Tophat 64 battens gave room to fit slightly compressed Earthwool R2.0HD 75mm thick acoustic batts in the cavity. It's not ideal to compress insulation but I figured it'd work better than loose R1.2 50mm thick batts which were the alternative.

I then screw fixed 12mm C/D structural ply to the face of the batts, sealed them with Feast Watson Proofseal and coated them with satin FloorClear poly. They're holding up nicely so far.

Not an exact fit for your situation as your column depth is greater but it might give you some ideas. More info and pics here if it helps: Tinkerer's workshop

Rather than start a new thread on this well worn topic, I have a query for those on here smarter than I.

I'm looking at lining my steel shed with yellow tongue flooring, most folks suggest battening out the existing metal frame work with extra timber studs, however my thinking is that if the boards are positioned vertically, with the board sitting on its end and the subsequent boards positioned adjacent, then there will be bugger all forces 'pulling' the boards from metal top hats/girts, to which they'll be attached?
In other words, most of the force will be directed straight down to the concrete slab the yellow tongue boards are sitting on, which to my mind will mean securing them to the existing top hats/girts will be adequate?

Any advice much appreciated.

Cheers.

That is almost how I did mine with MDF, i put a shim under each board to keep the sheet off the floor though and then removed the shim once the sheet was fastened. They are all still up there!


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Originally Posted by SparkyJack

Rather than start a new thread on this well worn topic, I have a query for those on here smarter than I.

I'm looking at lining my steel shed with yellow tongue flooring, most folks suggest battening out the existing metal frame work with extra timber studs, however my thinking is that if the boards are positioned vertically, with the board sitting on its end and the subsequent boards positioned adjacent, then there will be bugger all forces 'pulling' the boards from metal top hats/girts, to which they'll be attached?
In other words, most of the force will be directed straight down to the concrete slab the yellow tongue boards are sitting on, which to my mind will mean securing them to the existing top hats/girts will be adequate?

This is basically what I did in the MW area of my shed which I insulated and lined with miniorb, and it is just Tek screwed to the top middle and bottom girts , there are no supporting verticals at the joins. However I doubt I would have done it if there was no middle girt to attach to.
RockwoolIns.jpg

Minior3.jpg

It depends what you want to hang off the walls. If you want to hang a few tools on a wall that will be fine but if you want to hang something heavy, eg a couple of shelves with chainsaw and bits and pieces, unsupported sheet goods will over time buckle the sheet out at the top of the shelf and inwards at the bottom of the shelf without some support behind them. Over time this means the shelf is not horizontal and it becomes a PITA. Bracing also may help with noise reduction since unsupported sheet goods tend to be very "drummy".

In small sheds hanging shelves off walls above about 1.3m and keeping the area below that has many advantages like, eg sheet good storage and being able to tuck machinery underneath. If a shed walls are not too tall sometimes a top and middle girt can be used to attach things like heavy shelving.

The welded steel frame for the shelves in the photo made from jarrah and SS mesh and my MW lathe tucks in underneath. The frame is supported from the top shed girt at 2.4m and pinned at the middle girt. The mesh shelving is used for MW lathe tool like chucks and specific tools that can partially poke through the mesh so they take up less room on the shelf.

topviews.jpg

The WW section of my shed is lined with gyprock most of which cannot be seen because most of the walls in that area are lined with cupboards but because there are plenty of wooden studs behind the gyprock I was able to attach my HD chainsaw shelves direct to the studs behind.

I've wondered this myself, thanks for asking the question SparkyJack.

If your girts and other structure is good, I also cannot see a reason why you couldn't do this. In fact, the shed we inherited when we bought the property (which I am basically lining again now) had 9mm ply in this exact fashion fastened all around the walls. It wasn't done properly, nor sealed behind it, so it became an attactive place for bugs to make their home, and some condensation to begin forming some mould.

Apart from a bit of a reconfiguration to doors and windows, as you can see from the photos above, we installed Insulshed 50 along all exterior walls and ceiling. Then down the bottom we installed an anti-vermin strip.

Once that is done, and you have no condensation issues, installing your Yellowtongue should be just fine. As Cal has mentioned, avoid the wood making contact with the concrete - you can shim it whilst you install as he did, or you can put down a tar based dampcourse and staple it around the bottom edge of your sheet - either will work.

Excellent info guys, much appreciated!

I would go the extra yards and install the studs, without question - your best (only?) chance is right now!. They only need to be Radiata but will allow so much extra weight to be hung off the YT sheets without the danger of the sheets bowing, and as Bob says they will be less drummy. One never can tell where the future will take them.....best allow for it now.