Martin's Small Work Shed

[martin.a.ball]

Fortunately I decided to put the frame together with screws, so it is all recoverable. I hadn't planned on making a mistake quite so early in the project but thanks for pointing it out now before I start wrapping the whole thing in breather membrane.

 

[martin.a.ball]

After a short holiday break, back to the summer project. I thought it best to fix the door frame, as spotted by Mike, so cripple studs and a new lintel cut to fit. The window will get the same treatment after the next trip to the timber yard.

Also made a start on the roof which will be the next post.

 

[martin.a.ball]

A bit about the roof. What I'm aiming for is best shown in Muzza's build thread on post 1183958. So a flat/pent roof with a small overhang on four sides.

The rafters are 150mm x 47mm CLS spaced at 600mm. The span is 2.4m. I cut the birdmouths with a jigsaw although I'm sure there must a better way and then used a spirit level to mark and cut both ends vertical with a hand saw. As the rafters don't align with the wall studs due to poor planning, I added an extra top plate all round.

And a close up on one of the better birdmouths.

 

[martin.a.ball]

In all the build threads I've read this next step is rarely shown. If the front wall and ends walls have been built as regular square frames then you are left with gap to deal with at either end otherwise the ladders for the roof overhang have nothing to rest on. With better planning I reckon I would have built the end wall frame to include the slope, but building a frame to fit was ok. A bit of experimenting with the mitre saw was good enough for the studs, the long cut at the rear had to be a hand saw.

 

[Obi Wan Kenobi]

Looking good and enjoying the build :wink:

Obi Wan ccasion5:

 

[HOJ]

May be a bit late, I have some observations, you have put the cripple studs up the side of the door, as Mike G outlined, but the lintel appears to have a gap above, it should be tight up to the wall plate, they are there to support the load from the roof joists.

You mentioned that you set your studs at 610mm on center, be aware that some OSB3 is actually less than 1200mm wide, usually about 1197mm, and is manufactured for timber framing, principally, for use with studs on a 600mm center, with an allowance for leaving a gap between joints.

I would also suggest not fixing timber studs up tight to the windows and doors, presuming you will be applying a vapour membrane to the external face you will not be able to fold it into the openings, I allways fit windows and doors after the membrane is applied.

 

[martin.a.ball]

Hi HOJ. Thanks for the comments, the timber yard says their sheet material is 1220mm but I'll find out later when I go and buy some sheets for the roof.

 

[martin.a.ball]

At each end of the roof a ladder arrangement is needed so that the final rafter extends by about 100m to give a small overhang. This was a lot harder to put together than I thought for a couple of reasons.

As I had been fitting the other rafters I must have been selecting the straightest timber because the timber left had a fair twist and I wish I had done the ladders first with the best timber. The second issue is the birdmouths sit the rafter slightly lower and I hadn't allowed for this when making up the end frame triangles so the cross members needed trimming to fit. Both ends needed a fair bit persuasion to come back to something close to square but I now have a complete frame for the roof to go on.

 

[MikeG.]

.......be aware that some OSB3 is actually less than 1200mm wide, usually about 1197mm, and is manufactured for timber framing, principally, for use with studs on a 600mm center, with an allowance for leaving a gap between joints.......

This varies with the manufacturer. I have just bought dome 9mm OSB3, and some 18mm OSB3 from the same merchant, and found that the 9mm stuff is 1200x2400 (ie no allowance for gaps), and the 18mm stuff is 1220x2440 (8'x4')!! Beat that for stupidity!

 

[MikeG.]

........

Martin, this still shows the lintel over the window opening to be unsupported. You have to think of a lintel as a beam, taking loads down to the foundation via a post underneath each end. As you have it at the moment, the only thing supporting that lintel, and the weight of the roof above, are the nails knocked in to its ends. You have supported the cill, which has no load on it, but not the lintel, which has (potentially at least), a reasonable load to carry.

 

[martin.a.ball]

Martin, this still shows the lintel over the window opening to be unsupported. You have to think of a lintel as a beam, taking loads down to the foundation via a post underneath each end. As you have it at the moment, the only thing supporting that lintel, and the weight of the roof above, are the nails knocked in to its ends. You have supported the cill, which has no load on it, but not the lintel, which has (potentially at least), a reasonable load to carry.

Its on the list, need to get some more 4x2 during the next trip to the timber yard

 

[martin.a.ball]

Good trip to the timber yard. I got some more 4x2" and finished the cripple studs for the window.

Timber yard were also good too their word, 18mm OSB sheets for the roof are exactly 1220mm wide and hopefully matches my 610mm centers. That will have to wait for couple of days sunshine as the EPDM roof needs to go down at the same time.

In the meantime I wrapped the walls with breather membrane, cut the openings and folded the membrane round the door frame studs. I then tried the door frame for a test fit.

In the various build threads I've read some people reckon this is enough if sealed with silicon, others go further and add some flashing. Does anyone have any good photos of how to make a tidy junction between the cladding and the door frame?

 

[HOJ]

What are you proposing to use for cladding?

 

[martin.a.ball]

Most likely treated shiplap boards, about 22mm thick. They will be mounted on 2x1" battens to allow airflow. I reckon they will need some sort of finishing detail around the doors and windows, in a similar fashion to finishing the corners.

 

[martin.a.ball]

In the previous post the eagle eyed might have seen I tried to add a fascia using some left over 6x2". I didn't have a single piece long enough so tried to join them in the middle, mainly because the timber yard was all out of 6x1" when I last visited.

This bugged me for a few days before I did what I should have done all along, took it down and bought a couple of long 6x1" boards for the front and the back.

Roof is going on over the next few days as the forecast is good.

 

[Obi Wan Kenobi]

It's coming along nicely Martin

OWK ccasion5:

 

[martin.a.ball]

18mm OSB sheets fitted to the roof and I used someones trick of hammering a nail between the boards to get a few mm gap for expansion. Cutting boards to width with a circular saw and a batten as a guide was a challenge and the evidence of twisting in the ladder arrangement for the rafter that overhangs can be seen in the left corner but I'm generally happy with the outcome. It is strong enough to walk on which is more than you say for most sheds.

The rolled up package is the EPDM from Permaroof ready to be laid out.

 

[martin.a.ball]

EPDM roof going on. The instructions said leave for 30 mins for the creases to drop out, but in hindsight it would have been better, and easier to brush out bumps later, to leave for much longer on a nice hot day.

The bulk of the sticking down is with a water based adhesive that can be applied with a roller.

The edges are glued up with a bonding adhesive which somewhere between green fairy liquid and radioactive waste. Good idea to wear disposable gloves and I just binned the brush after, forgot to take a photo because of sticky hands but here is the end result.

I've left the overhang for the time being as I plan to glue the EPDM to the fascia but need to figure out the junction with the soffit, insect mesh and walls. Whilst I remember, does anyone have any recommendations for insect mesh? It doesn't appear to be stocked by the local DIY merchants.

 

[MikeG.]

I've not used either of these companies, because I have been using up some really old stock.......but I did notice them whilst looking for a specification for a client.

Here and here.

 

[HOJ]

For the insect mesh to the bottom and top of the cladding, I use the starter strips and ventilation profiles from James Hardie:

For example: www.squaredealupvcshop.co.uk/product/hardieplank-starter-strip-with-ventilation/