Workshop Build

[celston]

So here we are then folks, my workshop build. The action took place over the last year, the old, damp concrete prefab garage went last September and it's just about complete now. I neglected to take any 'before' shots of the garage

But the first job (before the garage could be demolished) was to build a set of double doors for the new building:

I've never made any doors before, I'm pretty pleased with the way they turned out (more photos later) This is the only photo I seem to have taken of the process - filling in the T&G. They're standard ledged and braced construction, and the right-hand of the pair is half-width and fully glazed. Essential biscuit breaks kept me going

A little in way of explanation about the site: the site is lower with respect to the surrounding ground level on two sides, so to the left and back of the new workshop I decided to use these existing walls to form part of the new structure. I had a builder come and build me further walls to the right and front to the same height as the left hand retaining wall. The design is a mono-pitch roof hard up against the neighbouring property which means I was restricted to 2.5m at heighest point, and under 15m^2 to avoid the need to conform to building regs.

It turns out that I'm pretty bad at remembering to take photos, so we've skipped ahead here a little already. Under the blue DPM is 50mm of polystyrene, both on the floor and up the brick walls. I was conscious that these would be potential cold spots, so I sacrificed 50mm of headroom for the sake of warmth. Any moisture coming through the retaining walls should make it's way down and under the building (fingers crossed!)

This photo shows the framing nearly complete. Double sole and header plates, sole plate is anchored down into the brickwork with tapcon masonry screws. The whole structure is toe-nailed together, checking for plumb and square as you go. I had the benefit of a friend for a couple of days to help out with the framing. Rafters are notched and nailed, the overall pitch is about 7% to give me the most usable space inside.

I think this is taken at the same time, but stood on the top patio looking down.

 

[celston]

This is the roof decking in place - 22mm OSB.

In this photo you can see the roof has been wrapped in yet more of the DPM to make it temporarily water-tight. That stayed in place until I got around to completing the roofing this summer!

Then the whole building was wrapped in breathable membrane, stapled into place. One (possibly) interesting detail - the retaining wall is 2 bricks deep, and the timber framing is 2"x4", so I chose to sit the framing on the centre-line of the wall. Which means that there is a 'step' on the wall inside the building. Here you can also see the lead flashing which will direct water running off the cladding away from the wall and frame. The frame itself sits on top of the DPM, to protect it from damp coming up through the
wall.

Here, vertical battening has been screwed to the frame uprights, and I've started to install the cladding. The cladding is Marley Cedral - which is a pre-painted cement-fibre board. It's moulded with a wood-effect surface texture, and in theory is good for 10 years without painting. It's not too bad to work with, although full boards (3.6m) are pretty chuffin' heavy. They also supply aluminium profiles in a matching colour for use at corners, edges and window reveals.

They're somewhat difficult to cut - I found the cleanest cut was achieved with a cheap hard-point saw but they blunt the blades pretty quickly. I think I went through 4 saws! Some cuts were also made with a grinder with a diamond blade - but this disturbs the painted surface and leaves a slightly 'woolly' edge compared to the saw cuts. You can buy special blades designed to cut these sorts of boards for use in circular saws, but I didn't have any luck in tracking them down. For example, Bosch do one for the American market but Bosch UK knew absolutely nothing about them.

More cladding progress.

 

[celston]

Only after attempting to hold and balance a board AND screw it into place for too long :roll: did I realise that life would be much easier with a pair of jigs to help me out. So here are those jigs in action:

Each jig is a length of 1mm thick aluminium with a hole drilled at one end and at the opposite end a small 'L' bent over. Then a sturdy block of hardwood screwed to the aluminum - the distance between the 'L' and the block gives you your board spacing, and the jig is temporarily nailed into place whilst the board is screwed into place. Then the nail is removed and the jig can be removed by pulling it down and out. You can buy similar fancy commercial jigs, but then that's not really what we're about, is it? (hammer)

I have what might be called a 'wiry' build (SWMBO sometimes unkindly refers to me as a "lanky streak of p*ss"), which is a good job, because cladding this side of the building was challenging even given that fact:

Things were tight but manageable until the point where the cladding reached about chest height for me, which then made manouvering myself, the board, an impact driver and screws a flipping nightmare. Several dropped screws and some healthy cursing! The impact driver was a new purchase specifically because it's shorter than my cordless drill, which didn't actually fit into the space (or that's how I'm justifying it, anyway...)

Here you can see the building from the top view again, with some tactically placed bricks to weather the atrocious storms of last winter. You can also see the soffits poking out from underneath have already been treated with Osmo oil (I forget which one, but it's an outdoor one with added white pigmentation).

 

[celston]

I think these 3 photos are my celebratory "Hooray I've finished the sodding cladding!" set. By this point I was very relieved to have done with it.

And here we see the set of double doors, fitted (as promised earlier!). I've struggled with fitting internal doors in the past, so I was mightily relieved that these actually went in with the minimum off fuss. No c*ck-ups, but I did have to spend a fair while staring at the lock rebate kit scratching my head before I worked out how it should all be fitted. I think I spent a good 5 minutes opening and closing the door in amazement.

Again, I think we've skipped ahead a bit here - no pictures of the floor fitting, which is a floating 22mm sprucefloor (T&G plywood). I did have a hard time trying to convince anyone to sell me it, they all had chipboard caberfloor in stock but not sprucefloor.

You can see that I'm a fair way on with the insulation here. Due to a quantity surveying c*ck up, it's a mix of rockwool and EcoTherm - I ordered too many EcoTherm (which was meant to be just for the roof), and not enough rock wool. All insulation is 100mm. Roof joists are 150mm, and the roof is a 'cold roof' design, so there's a 50mm ventilated gap above the insulation and below the roof decking. In the walls, the 100mm fully fills the cavity and the battens which the cladding are on give a 35mm air gap behind the cladding.

 

[celston]

Here you can see the jiggery, and indeed pokery that I had to employ in order to provide something to clad the inside of the rear wall. The entire bottom half of the wall is just DPM over polystyrene over damp retaining wall - so fixing through any of that would pierce the DPM and lead to problems later on. So I constructed a framework of 2"x4" "hanging" off the upper timber framing and tied into the sides to give me something to fix an internal wall to.

Finally the tools and tat have made their way out of the dining room and into the workshop (I really do have a very patient and understanding t'other half!). Hey, it can't all be riveting building details, eh?

A view from the inside with the yet-to-be-filled window hole, and the armoured cable running up and into the building.

I lined the inside with vapour barrier before the internal cladding went on - it's gaffer taped to the DPM, hopefully :mrgreen: providing a continuous vapour barrier on the inside. (Has anyone else noticed the review of this vapour barrier on screwfix by some chump who's bought it instead of DPM and is complaining that it's thin and hard to work with)

 

[celston]

Another jump in time - the internal cladding has been finished and given several coats of white emulsion. Notice the boxing in around the bottom foot and a half of the room - this is where the wall insulation projects into the workshop a bit. Again, the boxing-in had to be done with no fixings through the DPM, so it's attached to a batten on the wall, and one on the floor.

And to complement the first doors I've ever made, the first window (hammer) The details I got from an excellent site which I can't now find - basically the rebate on the outside is sloped for run-off, the bottom glazing bead is also sloped, projects beyond the edge of the rebate and has ventilation underneath to allow airflow and drainage out from the bottom of the window. The side glazing beads intentionally stop short of the bottom so that end-grain isn't sat in water wicking it up.

Here we have the hole for a skylight (one of three) being cut. The skylight windows (http://www.sterlingbuild.co.uk/product/ ... tAodpzUAuQ) were a poor impulse buy on my part early on in the project, which caused me much additional work (but hey, they were cheap :roll. They're not designed for such a shallow pitch, so I ended up having to make 3 frames to attach to the skylight frames to project through the roof and cant them over to the required 15%. I'm also not terribly impressed with the quality or security (hinges are screwed from the outside) - I wish I'd spent a little more on something better. I've improved the security a little by adding bars to the frames, which should hopefully dissuade anyone from prying them open to get inside.
Here's one of the boxes I made being glued to the skylight frame:

 

[celston]

Another big jump in time here - the roofing material has been laid and the skylights fitted. I priced up the materials for torch-on felt roofing and EPDM (rubber) roof. Rubber roof came out cheaper, and it seemed like it would be easier to get right for a novice. I'm really pleased with how it turned out - it's water-tight and it doesn't look awful. The process is pretty simple: the rubber is just laid in place, pull back half, apply glue, roll back half onto glue, pull back other half, apply glue, roll back onto glue. Then knock in some edge trim and you're done.

I had previously cut the holes for the skylight boxes, and then fixed the board which came out of the hole back in place. Then I was careful not to glue the rubber to those spots. When it came to fit the skylights, I just removed the boards from underneath and cut an 'X' in the rubber, and poked the skylight boxes through. Then on top you ahere the rubber to the projecting box and bond on some sort of 'patches' to cover the corners and make watertight. No leaks yet (fingers crossed!)

And here we are a few weeks ago. On the floor you can see my router table top in clamps (I can't remember which number of my 3 attempts to get something suitably flat that one is :roll

The table saw is on the mobile saw/router table workstation I've been building for it - which is very nearly complete now.

And that's your lot folks. It's been a busy 12 months for me, lots of hard graft but I've really enjoyed it. I hope you've enjoyed reading along. Any questions?

 

[The Bear]

Great job in a slightly unusual space. Everyone loves a workshop WIP.

Mark

 

[John15]

Very nice indeed Celstron. I hugely enjoyed reading the progress of your new workshop.

John

 

[devonwoody]

Could you post me more details on the flooring, a neighbour has taken up a shed floor which went rotten, I suggest he lays a sheeting likes yours and then what did you do?

 

[celston]

Could you post me more details on the flooring, a neighbour has taken up a shed floor which went rotten, I suggest he lays a sheeting likes yours and then what did you do?

It's Wisa Sprucefloor: http://www.laver.co.uk/files/mydocs/dow ... efloor.pdf
My local Travis Perkins didn't have it in stock, but ordered it in for me: http://www.travisperkins.co.uk/p/22mm-s ... 04/3893617

 

[devonwoody]

thanks re flooring,

so you laid a screed over the membrane and left the battens laying on the screed or did you fasten down?

 

[Vic Perrin]

What a cracking Workshop. You could live in there!

=D> Vic =D>

 

[PAUL_TDI]

Very nice build, really like the skylights, maybe because I could do with some more natural light!

Funny how you ripped a concrete prefab down, I've just put 1 up! Although after seeing all these lovely, brick/timber builds I think I've been inspired for my next house.

Not to be rude or nosey but how much would you say the build has cost you if you don't mind saying?

How big is it?

 

[Roughcut]

I very much like the double door and the skylights.
Overall the workshop is pleasing on the eye and fits well into it's environment.
Great job.

 

[celston]

so you laid a screed over the membrane and left the battens laying on the screed or did you fasten down?

No battens, no screed. 50mm insulation laid on the floor of the original garage (which was still sound), then DPM, then sprucefloor floating on that (with t&g glued).

 

[devonwoody]

Thanks Celston for the reply. You obviously have trade experience so this is a learning situation to me.

 

[Wizard9999]

Celston

As others have said, a very nice build. I am about to start a workshop build myself and a lot of helpful details in your posts, so I will be referring back in due course.

However, one question for now. I like the idea of skylights and despite it being to remedy an issu I actually really like the look of the skylights as you have fitted them. However, you (as I will be) were limited to 2.5m due to being on the boundary (I seem to recall height is a planning issue rather than a building reg's one) and I wondered if you were able to contain the raised boxes such they were still below this maximum height? If so, are you able to share details of the dimensions of the raised boxes you created for the skylights?

Thanks,
Terry.

PS as a 'tub of lard' I can only envy anyone who is described as a 'lanky streak of p*ss'!

 

[pip1954]

hi celston
very nice job should be cosy in there.
where did you get the marley cedral from and what price did you pay am thinking of doing outside of my bungalow with it was it easy to find
pip

 

[celston]

However, one question for now. I like the idea of skylights and despite it being to remedy an issu I actually really like the look of the skylights as you have fitted them. However, you (as I will be) were limited to 2.5m due to being on the boundary (I seem to recall height is a planning issue rather than a building reg's one) and I wondered if you were able to contain the raised boxes such they were still below this maximum height? If so, are you able to share details of the dimensions of the raised boxes you created for the skylights?

Sorry for the delay in getting back to you on this. It's been a busy week!

I've just sketched the following diagram, which I hope explains things a bit.

The rooflights came with a wooden frame which is 70mm deep, this was then attached to a box I made which was 250 deep. I then removed enough from the bottom of that box to give it an 8 degree slope (i.e.: 7 degree roof pitch + 8 degree box slope gives the 15 degree stated minimum for the rooflight). You can see from the diagram that that meant the box is 250mm at one end and 180mm at the other end.

So, on to whether this falls within the 2.5m height. I just nipped out and measured the projection of a rooflight above the roof deck (vertically), and it comes to 170mm (line A-B on diag.). The point A is 1540mm downslope of the apex of the roof. If the distance A-C is > 170mm, we're in the clear. I know the roof is a 7 degree pitch, so using trig: A-C = 1540 x sin 7 = 187mm (approx) Phew!

In fact, this is something I played around in sketchup with for quite some time, and it's the reason that all 3 skylights are on the lower side of the pitch.

Cheers,

Chris.