Nails and screws for Garden Shed construction?

[cutter12]

Hi,

I am trying to design a 12x10' shed for the Garden (hammer) . I plan to use 4x2 for the walls and 6x2 for the rafters and floor joists. 18mm Ply floor. 3x2 purlins. Galvanised roof with 3 PVC sheets for extra light. To try and offset any condensation problems i am going to hav lots of ventilation at the eaves and ridge.

I have worked out the timbers sizes and overall design but am really struggling to work out what screws and nails to use and where to but them. Many of the resources i have been using are American and for the 2x4 stud work they recommend 16d (89mm) and 10d (75mm) nails. 75mm seems to be a common size but 89mm is elusive, do I just use 100mm instead?

I am using Treated Timber and from what I understand I need to use either Hot Dipped Galvanised or Stainless Steel Nails and Screws as the timber is somewhat corrosive. I also live by the sea so anything that resists corrosion is going to be better.

Screwfix sell galvanised nails but I think they are just the elctroplated ones (Screwfix Support say they ahve a 12 Micron coating?) ( www.ie.screwfix.com/round-wire-4-5-x-10 ... -pack.html )

They also sell some 'Timbadeck' Stainless Steel Screws ( http://www.ie.screwfix.com/timbadeck-co ... f-100.html ) but they get some poor reviews regarding strength.

Has anyone got any thoughts or recommendations on what I should use to fix the various shed components together? :

- Stud Framing
- Plywood floor to Joists
- Purlins to Rafter
- Metal and PVC Roof to Purlins


Thanks

Jon

 

[rbland]

As nobody has answered yet I may as well have a crack.

For stud framing I’ve always used screws driven through the plate into the stud. Depending what grade of treated timber you have will determine how deep the treatment penetrates. If it’s the treated kiln dried regularised timber you get at most builders merchants, the treatment doesn’t penetrate very much so the shank of your screw doesn’t really come into contact with the treatment chemical. I’m a big fan of torx screws from Toolstation. They’re not for exterior use, but stud fixings aren’t exposed to the elements so it’ll be fine. None of my walls/sheds have fallen down yet… If you’re going through 2” thick go for 80mm long at least. You can use nails if you prefer, but I like how screws pull things nice and tight and you can correct twist and line up a stud with one hand whilst driving the screw in with the other. It’s also easier to correct a mistake with screws.

Nails are used for certain applications because they’re more ductile that screws e.g. joist hangers should be nailed. Studwork small shed walls aren’t really subject to shear loads big enough to shear a 5x80 screw so it’s not really an issue.

For ply floor to joist, screws again, 5x30 or 40 would be fine.

Purlins to rafter – screws again.

For the metal roof to purlins you can get roofing screws. These are generally a pan head screw with a plastic cap. The lower part of the cap seals against the roofing sheet and an upper cap clips over the top of the screw head. You can get these colour matched to your roofing sheet. Don’t get confused with roofing screws which are intended for use with metal purlins – these screws usually have a hex head and are self-drilling. The ones you want are basically a woodscrew with plastic cap – some of the better quality ones also have a rubber washer beneath the screw head.

e.g.
http://www.screwfix.com/p/hardened-stee ... pack/21886
or
https://www.toolstation.com/shop/Screws ... rew/p51734

Is this to be a workshop or a storage shed? The reason I ask is because the timber sizes you specify are rather heavy duty for a storage shed. My 12x14’ workshop is framed with 2x4, but I framed my smaller timber storage building with 2x2. It’s got about half a tonne of timber hanging off the walls and its fine. You could potentially step down to 2x3 for studwork, 2x4 for floor joists (depending on how you plan on supporting these), 2x4 for rafters with a tiebeam and 2x2 for purlins. Also you could substitute the 18mm ply for 18mm OSB3 as it’s about half the price yet still structural and moisture resistant. If cost isn’t an issue and you want a really sturdy building then there’s no harm in sticking with what you have.

 

[Benchwayze]

I have used coach bolts, from that fixing place that sends you screwy leaflets all the time. They call them turbo screws, but they are just passivated coach-screws, with hexagonal heads and built in washers. They drive home well, and and haven't rusted so far. My shed (when it's done) is just a standard, off the shelf model, made from the usual lightweight carp. Although there ain't no roof on it yet,it's still resisting wind movement! Just...

I am in the process of binning it mind, as it's not the proper job I thought it was. It would be fine for a potting shed, maybe. But I want to design my own, more sturdy building, before the autumn sets in. I'll be using 50mm sq pressure treated stuff for the framing and 75 x 50 for the rafters and floor joists. Ample for a 10 x 6 shed that will be used for a hand-work shop. I will be using metal siding to clad it, as the best place for my shed is too close to the house for Walsall's planning rules on wooden clad buildings.

HTH

John

 

[undergroundhunter]

I've just re-roofed a brick shed using treated timber. My father in law a retired joiner of 30 years suggested nailing it it together, I on the other hand prefer screws for the reasons listed above. I bought a tub of green decking screws from one of the big box stores, I have used these in the past so know that they are 1 designed for use with treated timer and 2 don't seem to corrode (probably due to their coating). I only used nails for the felt.

Matt

 

[Phil Pascoe]

If you'd ever tried pulling out annular ring nails you wouldn't worry about using nails.

 

[cutter12]

Wow. Thankyou all for the feedback . Very good to get some input

If you'd ever tried pulling out annular ring nails you wouldn't worry about using nails.

I might use the Ring Shanks for the Shiplap?

I've just re-roofed a brick shed using treated timber. My father in law a retired joiner of 30 years suggested nailing it it together, I on the other hand prefer screws for the reasons listed above. I bought a tub of green decking screws from one of the big box stores, I have used these in the past so know that they are 1 designed for use with treated timer and 2 don't seem to corrode (probably due to their coating). I only used nails for the felt. Matt

Yes, Decking Screws do seem to be good value and resist corrosion. These could be a good option for the Ply Floor. I guess I have to decide what shear strength I really need for the other tasks? As rbland says, the screws pull things together really well.

I have used coach bolts, from that fixing place that sends you screwy leaflets all the time. They call them turbo screws, but they are just passivated coach-screws, with hexagonal heads and built in washers. They drive home well, and and haven't rusted so far. My shed (when it's done) is just a standard, off the shelf model, made from the usual lightweight carp. Although there ain't no roof on it yet,it's still resisting wind movement! Just...

I am in the process of binning it mind, as it's not the proper job I thought it was. It would be fine for a potting shed, maybe. But I want to design my own, more sturdy building, before the autumn sets in. I'll be using 50mm sq pressure treated stuff for the framing and 75 x 50 for the rafters and floor joists. Ample for a 10 x 6 shed that will be used for a hand-work shop. I will be using metal siding to clad it, as the best place for my shed is too close to the house for Walsall's planning rules on wooden clad buildings. HTH John

I hear what you are saying John. I have loked at lots of sheds and they are often pretty lightweight. But then again they last for years and do what they are supposed to. I have considered buying the cheapest shed possible but for some reason can't bring myself to build one to the same lightweight standards. I think maybe because I would be held reponsible if it fell to bits

Is this to be a workshop or a storage shed? The reason I ask is because the timber sizes you specify are rather heavy duty for a storage shed. My 12x14’ workshop is framed with 2x4, but I framed my smaller timber storage building with 2x2. It’s got about half a tonne of timber hanging off the walls and its fine. You could potentially step down to 2x3 for studwork, 2x4 for floor joists (depending on how you plan on supporting these), 2x4 for rafters with a tiebeam and 2x2 for purlins. Also you could substitute the 18mm ply for 18mm OSB3 as it’s about half the price yet still structural and moisture resistant. If cost isn’t an issue and you want a really sturdy building then there’s no harm in sticking with what you have.

Its going to be half storage and the other half willl have a bench and vice. You are right I should consider using less heavy timber as a cost saving would be welcome. The floor was going to be 2x6 Joists at 16" OC resting on 2x6 Mud Sills (x3 one at each side and one down the middle running perpendicular to the Joists). The foundation is made up of 12 concrete blocks (3 rows of 4). Do you think that it would be acceptable to swap those for 2x4?

When you say 'tiebeam' is that the same as a Ceiling Joist (runs from the top of one wall to the opposite wall)? I was going to put in two 2x6 for that purpose but maybe that is overkill? I understood that I needed it to stop the walls from being pushed apart? I am trying to keep the hieght of the shed down so the 2x4 would help with that. All the info I have read seems to be for designing a very sturdy shed which seems to be at odds with the Garden Sheds commonly for sale. Would 2x4 rafters be OK for a 5ft Run?

I think what I am finding hard is trying to build such a large shed (12x10) as all the spans seem to require beefy timber. In someways I could manage with a smaller shed and would prefer to have my bench just under a lean to shelter (a bit like a carport) as it would suit how I work better. I am no Fine Woodworker and having open sides would be great for bigger pieces of wood and also great for using dusty power tools as I would go outside to use these anyhow. Maybe I need to rethink the whole design :? A lighter wieght single pitch shed with a lean to might work better? ...but then I would maybe need concrete pier foundations....

Thanks for all the advice on the screws. Really helpful. For the Metal Roof I was going for just plain old Galvanised so any colour would do. Have you ever used that? I did get a bit worried about condensation and rust.

OK. I think I have my head around the screws and nails. Now to redesign the shed.......

 

[AJB Temple]

In all probability personally I would use timberfix flange hex head screwbolts banged straight in with an impact driver. We have today driven in around 140 (mixed 100m and 150mm) putting up a roof made of oak rafters. These are fast to fix, will not rot and are structural. No pilot hole needed. Very strong.

Fix mesh in your ventilation gaps or you will have vermin / birds.

 

[swnyradar]

I would go with treated OSB for the roof with bitumous corrugated sheeting nailed to that as I found iron sheets tend to form quite a bit of condensation during the night. Also venting through the eves without some form of mesh will cause bird/vermin problems. I found quite a few overwintering wasps in my big shed when refurbishing it last winter.

 

[cutter12]

I would go with treated OSB for the roof with bitumous corrugated sheeting nailed to that as I found iron sheets tend to form quite a bit of condensation during the night. Also venting through the eves without some form of mesh will cause bird/vermin problems. I found quite a few overwintering wasps in my big shed when refurbishing it last winter.

Yes, I was a little concerned about the potential metal/condensation problem. What thickness of OSB3 did you use btw? 18mm? Also di you use the screws or the nails for fixing the bitumous sheet down?