Thread: Inner shed framing

I'm actually planning exactly the same thing. Perhaps there's something over in that thread? Simon's New Shed
And lots of details in Midnight's thread Midnight's Shed

Yes Midnight's shed covers it and I have read that twice. I guess I want to have my cake and eat it too. His shed is 10m x 7m = 70m2 and I shudder to think what all that framing cost him. Mine will be 18 x 10.5 = 189m2 or even longer if I can afford it. So I have sunk all my money into the size of the shed and now I am facing the inevitable problem of not having allowed for the fit out. His construction did seem to me to be over engineered. Yet of excellent quality. So I guess I was aiming for the same outcome but trying to cut a few corners.

For example his frame timber is 90 x 45. He has all that metal strapping. So I thought I could get away with 70 x 35 timber and perhaps look for a cheaper way to stop the batts from falling out. I was also thinking about leaving out any noggins and just having one diagonal metal strap to hold it together until the sheeting goes on. Although I think one row of noggins would be required in reality. It will be strong and rigid once the sheeting is screwed on and its bolted to the steel frame and floor. When I say strong - it is not structural so I mean strong enough to hold up cabinets and stuff.

Then I got to thinking about how I need a mezzanine at the rear of the shed so am I just kidding myself with this flimsy frame idea?

My shed walls will be higher than his and another advantage of the way Midnight has done it, is that his design could easily support a solid storage shelf on the top of the frame right around the shed. And I do have a timber hoarding habit to feed.

Timber is unnecessary, look into metal stud and track, like this Walls | Rondo
Heaps cheaper, easier, and no problem with humidity causing issues with mould and rot. The price of timber now is ridiculous, if you can get any.

I think my usage/cheapness is closer to yours than Midnight. My shed is similar to yours (16x8m at 3.6m eaves), but I got the builder to do the mezzanine (steel framing) down one end. The thing I'm most worried about is condensation on the shed walls creating mould, and perhaps adding some thermal insulation to the walls. I don't think I'm ready to tear off all my external cladding to add Insulshed "properly", so am trying to figure out a plan-B.

Originally Posted by riverbuilder

Timber is unnecessary, look into metal stud and track, like this Walls | Rondo
Heaps cheaper, easier, and no problem with humidity causing issues with mould and rot. The price of timber now is ridiculous, if you can get any.

How does steel framing help with the issue of condensation causing mould? Sure, the framing itself won't rot, but if it's that bad, the ply would probably suffer also.

Originally Posted by lyricnz

How does steel framing help with the issue of condensation causing mould? Sure, the framing itself won't rot, but if it's that bad, the ply would probably suffer also.

Yes true dat. Although to be fair a shed has huge open roller doors and some rain can come inside. Also mould will gradually turn to rot in time.
I think the main concern we all have is condensation causing mould, which we wont see behind the lining. I live in SE QLD and so it is a humid climate.

But yeah I plan to line it with melamine and so I couldn't allow that much condensation anyway.

The price of timber has shot up but then so has the price of steel. My shed has shrink 3 times already before I have managed to get the finance sorted due to price increases.
My had heard that timber is starting to head more towards normal as supply v demand has started to ease. Is that true or is it still a bit insane? I'm hoping it will be true in another 6 months or so.

I'll look into steel frames but as a DIYer at least with timber I can custom everything to fix my mistakes.

Originally Posted by DaveVman

Yes Midnight's shed covers it and I have read that twice. I guess I want to have my cake and eat it too. His shed is 10m x 7m = 70m2 and I shudder to think what all that framing cost him. Mine will be 18 x 10.5 = 189m2 or even longer if I can afford it. So I have sunk all my money into the size of the shed and now I am facing the inevitable problem of not having allowed for the fit out. His construction did seem to me to be over engineered. Yet of excellent quality. So I guess I was aiming for the same outcome but trying to cut a few corners.

For example his frame timber is 90 x 45. He has all that metal strapping. So I thought I could get away with 70 x 35 timber and perhaps look for a cheaper way to stop the batts from falling out. I was also thinking about leaving out any noggins and just having one diagonal metal strap to hold it together until the sheeting goes on. Although I think one row of noggins would be required in reality. It will be strong and rigid once the sheeting is screwed on and its bolted to the steel frame and floor. When I say strong - it is not structural so I mean strong enough to hold up cabinets and stuff.

Then I got to thinking about how I need a mezzanine at the rear of the shed so am I just kidding myself with this flimsy frame idea?

My shed walls will be higher than his and another advantage of the way Midnight has done it, is that his design could easily support a solid storage shelf on the top of the frame right around the shed. And I do have a timber hoarding habit to feed.

I'll try go through your post to give you some ideas on costs. Bear in mind prices now are not what they were then - my build began 2 years ago (what can I say, I'm time poor).

Also, all the quantities and measurements here apply to my shed, they won't apply elsewhere.

First note - find a builder's hardware supply place near you - most will happily sell to retail/DIY, and get yourself set up with them. Product quality is better, and prices often keener (and you're supporting a little bloke rather than the Wesfarmers conglomerate).

Also noting that when you do a project like this over a long period of time, you spread the cost, and it's more palatable that way (not suggesting you should, simply noting that we did out of necessity). It's probably going to scare me when I realise how much we spent, as I've never figured it all out...

Framing: I dug out an old invoice, and found I was paying $3.90 a metre including GST. In ballpark terms, each frame is about 3.2m x 2.4m, so it consists of 3 x 3.2m for top, bottom and noggins for a total of 9.6m. Around 7 studs per frame @ 2.4m each comes to 16.8m, so the overall total per frame is 26.4m of framing material. Add 10% (offcuts, wasteage) and you get to 29m per frame. Back then that would cost $113.10 per frame, and there's 10 frames. Would have come to a total of $1131.00 roughly. In todays price, it's about $6.10 per metre, so it would work out to $176.90 per frame, or $1796.00 overall.

Builders wrap: A roll of 2750mm high and 25m long wrap is about $150.00. We needed about 1.5 rolls, so this would now come to $300.00 - we actually paid about the same price a couple years ago.

Metal strapping: This is one product we got from Bunnings. No idea of what we paid, but here is the current product and price: Abey 25 x 0.6mm x 30m Punched Metal Strapping - Bunnings Australia From this you will get about 12 x 2.4m straps, which is enough to complete one frame. So the total cost of strapping for us was probably around $225.00 (I don't suspect this product has changed in price much). You also need a tensioner for each strap. These are pretty cheap now, as they were then (but quantities add up!). Expect to pay $3.10 for each one, and we used 12 per fram x 10 frames = 120 tensioners for a total of $372.00.

Insulation: We're using 88mm Bradford SoundScreen - R2.5 @ 1160mm x 580mm x 88mm. Back then, as now, it's around $50.00 per pack. On average, each frame takes 12 pieces, and each pack contains 7 pieces. A total of 120 pieces needed, thus we bought 17 packs (from memory/theory). 17 packs at $50.00 each comes to $850.00

Lining: TradeMasterJoinery Okume Plywood in 15mm was costing us $35 a sheet. If I recall and calculate correctly, we would have bought 45 sheets (we're building a dividing wall, which takes extra material). This would have come to $1,575.00 for the lining. Today this same material isn't available - they don't have Okume ply in stock (whether that's permanent or not time will tell). You can get non structural ply from them in 15mm thickness for $49.50 per sheet, which would add a good amount to the total cost - it would now be $2,227.50. I also have no idea how "good" the non-structural ply is in terms of appearance.

So, whilst prices have changed a bit, our build (framing, straps, tensioners, builders wrap, insulation and plywood cladding) would have come to around $4150.00. I think for what it is, and what we can get out of it in terms of longevity, function and use, that's pretty good going. In all honesty, the bigger ticket items in this so far have been the floor ($3000 to have levelled, $2000 for epoxy finish). Ceiling cladding might get scary in terms of cost (I am *still* trying to figure out a solution). Lighting will add a good chunk to costs. Electricals, I will admit, are going to be also overengineered, but will not need to be touched again. So far it's consumed around $700 of cable alone, and hasn't got a switchboard or power point yet...

A couple of thoughts to finish with, having gotten to where we are in our build.

Leaving out noggins would mean your insulation batts would be less supported, and I wouldn't want to have done our fitout in this way - whilst the noggins do add a level of cost, they're mostly made up of offcuts anyway.

Try to stick with standard framing layout dimensions if you can, things like insulation batts and cladding come in certain sizes for a reason, and they work together using standard measurements. FWIW our studs are 600mm on centre. I cannot foresee any reason to go less than this - I can hang on to, and shake the crap out of the top of one of our frames to no effect. You were also right when you mentioned in your post that I was thinking ahead to hanging cabinets and French Cleat - what we have built is the same as inside any house, which have kitchens that support overhead cabinetry etc, and I was aiming for strength. And yes, a comment you made (here or elsewhere, sorry, can't recall) - I have probably overengineered to a degree. But it beats regrets.

Hope this helps!

Thanks Midnight. Extremely useful reply!

I was thinking of using the same sound batts. I just noticed you said they are 88mm. Therefore a 90mm frame is required. Something for me to think about.

Originally Posted by DaveVman

I was thinking of using the same sound batts. I just noticed you said they are 88mm. Therefore a 90mm frame is required. Something for me to think about.

You can get a version of these that suit 70mm framing. But naturally, their thermal and acoustic performance is reduced accordingly. I don't have figures for acoustic performance, but the thermal performance on the 88mm is R2.5, whilst the 70mm is R2.0

Please also note, if you end up using metal framing, there is a different size of batt that is used - see here for more: Bradford SoundScreen, Australia's most trusted acoustic insulation - Specifications

EDIT: I found this link: https://www.architectureanddesign.co...ttachment.aspx

This specifies the following acoustic performance:

CSR 305: Std 110mm internal plaster wall construction, 90mm timber stud frame at 600mm centres, both sides 1 x 10mm Gyprock standard recessed edge plasterboard, with:
a) No insulation Rw32
b) R2.0 – 70mm SoundScreen in the stud wall cavity – Rw42
c) R2.5 – 88mm SoundScreen in the stud wall cavity – Rw43

So, what does Rw32, 42 and 43 mean?

From this link: Acoustic FAQ's - Fletcher Insulation.

A Weighted Sound Reduction Index or Rw, is the rating used to measure the level of sound insulating abilities of walls, floors, windows and doors. It is expressed in decibels (dB), and is used for a partition or single component only. The higher the Rw figure, the better the sound isolation that is provided.

If I read this correctly, the a typical 90mm stud frame with 10mm gyprock on either side would be the same as wearing ear muffs (i.e. hearing protection) rated at 32dB reduction (or, this product: 32dB Supreme Ear Muffs | PPE - Safe-T-Rex Workwear Pty Ltd)

Using this source: What is Rw? - Viridian - We Love Glass I am led to believe that if I stick a CV Max that normally howls at 95dB inside an enclosure made of 2 x 10mm gyprock over 90mm studs and fill the void with 88mm Soundscreen, I should end up with an outside-of-enclosure noise level of 52dB (assuming there is no other way for noise to egress the cabinet - which there will be - but you follow the logic).

I would actually dearly love to know if that is correct - because it will seriously alter my plans for my dust extractor enclosure if so!

It then follows that the difference in acoustic performance between the 70mm and 88mm product is not so great, there is "only" 1dB difference. I say "only" because I have heard that 10dB increase in noise doubles the noise level we hear, thus a 1dB reduction is not completely insignificant if this holds true.

Or, I am completely barking up the wrong tree, and am about to learn something new based on feedback in this thread

I wouldn’t bother with metal bracing, apart from the walls being only partition and not structural the plywood lining will make them more than strong enough.
Likewise there is no real need for noggings if you don’t want to install them in this type of scenario.You could consider using steel rondo partition stud and track as Riverbuilder suggested if that floats your boat. It will work just fine.

I don't know about the Rw value. I was looking at the kg/m3 value. However I don't know what the larger mass density value converts into in terms of reduced decibels.

I don't know about this stuff, but I can't see how a 32dB reduction from 95db could be the same as a 32dB reduction from 60db. Being a non-linear scale how could that 32db reduction apply to any db noise level? My guess is that the 32dB reduction for hearing protection, indicates 32db difference from some nominated ambient level in the standards. However as I say - I know nothing!!! It's all a confusing mystery which leaves me bewildered to me to be honest.

Originally Posted by DaveVman

Being a non-linear scale how could that 32db reduction apply to any db noise level?

See? Told ya I could be barking up the wrong tree. I didn't realise it was non linear

Yeah db is very non-linear. It's a ratio on a logarithmic scale. However it does not necessarily follow that some db noise reduction value could not be applied anywhere on the scale. Sorry - double negative.

What I mean is that maybe a 32db reduction from materials can apply anywhere on the scale, may be not. Because 32db is a ratio maybe it does. But how does the physics of the material have the same ratio effect at any level of a logarithmic scale? I dunno! That makes little sense to me. Perhaps that is just how sound transmission works? Maybe it doesn't. Dunno!
For example, going the other way, an amplifier, amplifies the signal by a ratio and that ratio is expressed in db.
I have no idea if sound reduction materials work that way or not.

So yeah - I'm just bewildered to be honest. What I know is I want to reduce the loudest noises coming out of my future shed.

I framed out the inside of my shed with standard 70*35 framing pine, filled the void with fibreglass insulation and used 5mm bracing ply as panelling.

I run aircon and can work inside at night without annoying the neighbours. With all doors shut, I can run the table saw and dust collector (CV1800) and you can barely hear it from the house which is about 15m away.

My shed build is here: My Shed build - finally! which also shows my mezzanine (I think).