New workshop build, with a difference!

[Cegidfa]

Hello all, thanks for the warm welcome a while ago; I hope that the pics work ok.

The 'difference' is twofold. Firstly, any 'idiot' can build a pitched roof :wink:
but it takes a complete numbskull to want a gambrel roof, having never built anything larger than a table before. Secondly, there will be no mention of SWMBO here as my wife Diane and I always work together on all projects.

As we never got to build our own house, the workshop build will be a modified house build, using similar techniques.
The pic below is a Sketchup representation of what we would like to achieve

http://img651.imageshack.us/i/2dshed.png/[img]

We have made a start and if I can get the hang of posting pictures I will post progress so far. Is a pic meant to show in preview? We think we have followed the instructions correctly! #-o

Regards Dick.

 

[mailee]

It is just the spam trap. After about three postings it will go away. I am looking forward to seeing the plans and the build too. Workshop builds are always interesting.

 

[Cegidfa]

Hello Mailee, thanks for the reply. I have to date posted six times to get over the spam trap. Perhaps I have got the code on Imageshack wrong, will try again.

Lets see if this works? [-o<

Regards Dick.

 

[Cegidfa]

\/ ccasion5: =D> Sorted.....Full steam ahead.

 

[mailee]

That's sorted it Dick. Whoo Hoo! that is one great looking workshop! I will watch this one with baited breath, looks like a great project to me.

 

[houtslager]

looking good, love to see the calcs for the roof timbers

 

[Mcluma]

That is indeed almost a house build

 

[wobblycogs]

Wow, you've got your work cut out there. I wish you the best of luck with it and I really hope you keep us updated on how the project is going. You say you've made a start, does that mean you've started digging holes or you've got a plan drawn up?

My partner and I work as a team too, she breaks things and I fix them (to be fair her plumbing, especially the soldered parts, is much better than mine).

 

[Cegidfa]

Hello Houtslager, in reply..err..so would I :shock: I know this sounds mad but let me develop my thinking in the main body of text, and then hopefully someone will put me right. You are right to question the calcs, as I can find no technical references on how to size a gambrel construction. They can't be the same as pitched roof can they?

Hello Wobblycogs, yes the plan is drawn, but open to change. Holes have been dug and concrete poured. My wife is also better at plumbing joints and far better at rendering and bricklaying than I am. It's about patience I think.
The good thing is that she understands the underlying principles in all that we do, so can see flaws or a better way of doing things when I am stuck for an idea.

Regards, Dick.

 

[softtop]

Looks like it will be a great, light space to work in - lucky you!

 

[houtslager]

here's a link to more info -
http://www.tractorbynet.com/forums/build-yourself/26098-gambrel-roof-angles.html

http://www.blocklayer.com/Roof/GableEng.aspx

http://homeimprovement-6.info/531699-How-to-Build-a-Gambrel-Roof.html

hth,

karl

 

[Cegidfa]

Hello all,
Having got the hang of posting, I should give you some idea of the size of the beast and construction method.

It will be sized to not involve planning or building regs and more importantly, too big for us to manage the weight of roof parts, etc...so, in essence, it’s a pussy cat to some of you and a tiger to others. I claim total absolution from the dread ‘green envy’ of the latter, we’ve been there.

The internal size will be 6.95 x 4.3 x 4 metres tall, 8m from the house and 3m from the dividing fence (steady the tigers).

As this is a faux house build, it will have a poured foundation, one row of 440 x 140 blocks and then four courses of engineering bricks up to the timber frame.
It will have a cast concrete reinforced base on a DPM, to the level of the first course of bricks. Simpson strong ties will be set in the concrete and tied to the studs, rather than the sole plate, as we regularly have strong winds head on. The max recorded is approx, 70mph and a regular 25mph (as I write).

The stud walling will be constructed from pressure treated 100 x 47, with a double header, as the roof timbers do not always line up with the studs. This is recommended by the Trada timber frame construction manual. I am using this as a guide as it is ‘only a shed’ with pretensions of grandeur.

The roof timbers will be 150 x 47, bearing in mind that we will be using asphalt shingles rather than tile or slate.

The reason for having four brick courses is that we are very adjacent to the Severn; 8m at ‘high tide’. It rises by 7m from normal levels, approx. three times a year, so we will build flood guards for the doorways, just in case. :lol:

If anyone can see any problems with the above, apart from building on a clay based flood plane :shock: , or at any time during the build, please advise.

Now for the drawing, by Diane of course.

 

[TrimTheKing]

Really looking forward to this build, looks really interesting.

Good luck.

Cheers

Mark

 

[jlawrence]

I can't believe at that size you can avoid either planning or building regs.

 

[Cegidfa]

Hello softtop, I hope it will be a light space, and as to lucky, I have to build it yet, not to mention work out how the hell to build three roof lights that don’t leak. Has anyone out there achieved that, and if so how?

Hi Karl, thanks for the links, as it happens I have seen the top one before and unfortunately blocklayer only deals with gable and hipped, not gambrel. The bottom one was a bit sparse but it did reinforce my idea to use 150 for the roof timbers but it gave no idea about what span that would suit....ho hum thats life.

Hi Mark (Trim), I hope I can do your interest justice.

Hi jlawrence, I hope we haven’t missed anything,which aspect is it that you consider is over the top regarding size? As stated the internal size is less than 30sqm and the height won’t exceed 4m, have we missed something? :shock:

Regards...Dick.

 

[Cegidfa]

Hello all,
Having had the drawing and an overview, now for the bit we all enjoy, the WIP pics.
I hope that I include enough info for other beginners like myself, who might be a bit hesitant to start their build; (it both scares the excrement out of me, but also excites in equal measure) and not too much for you pros. If more detail/help is required please feel free to ask and I will do my best.

This is the area after two tonnes of gravel have been raked up and bagged.
We were then left with compacted gravel over rubble, in blue clay.

Next the profile boards were laid out and nails fitted to mark positions, not forgetting to measure across the diagonals to check for square. This took a bit of time to get right but is worth it. We had a daymare trying to bang in the posts, so they are not nice and square to each other, but still did the job.

Having run the string out, we spray marked the lines so that the string could be removed for the joy of pick axing the trench. It is definitely worth buying the pukka stretchy line for this, as far more tension can be achieved with it. This also applies to the bricklaying line. It makes the job far more accurate and, as a result, easier for us beginners.

Metal pipe was banged in every 1200 to mark the depth for the footings concrete and then poured using ready mixed. There is not a problem wondering about which mix, as they always ask what it is for. Once poured, the string was replaced so that the corners could be marked out and lines snapped. These were reinforced with scratched lines made with a pointing trowel.

We were advised to use use wider blocks before going to bricks, to give more stability.
Strewth, 440 x 140 x 215 blocks are just about my limit when dropping them in a hole. Boo boo number one......make the trench wide enough to stand in, doh! That’s what comes of being a cheapskate. Trying to manoeuvre the blocks onto the mortar was ‘fun’ with a small f; dropping the blocks squeezed out the mortar. Diane to the rescue, she suggested using a clamp at the joining end to better control the lowering. It worked a treat and we got on a bit faster. That is to say, a fast snail, not a slow one. See the results below.

We also flaunched the sides of the blocking with concrete to both hold the blocks firm and aid water run off into the gravel faux french drain. Stop smirking you pros, we are just a pair of numptys with a bit of common sense :roll: :wink:

Well, that’s it for now, please let me know if the style is a bit too like a Haynes manual.
The aim is to help others, but with a bit of levity. Dibs-h is my hero, in that his build was informative and a good read; not to mention that he did it largely on his own. =D>

TTFN ....Dick

 

[cmwatt]

Interesting design, looks similar to one here: http://www.woodworkersinstitute.com/forum/forum_posts.asp?TID=970&PN=1

Might be a worth a read through to help you get an idea of what's involved. I take it your build is a single storey? Looks like a good start so far, very tidy site so far as well...

Craig.

 

[Dibs-h]

Looking good Dick. I envy you in that there is 2 of you doing it. Wifey don't do blockwork\digging. :roll:

Looking at your drawings - my feeling is that with the wind loads in your neck of the woods - you may need collar ties on every "rafter", not every 2nd one.

What's the pitch of the upper part of the roof? Most roof coverings have a minimum angle below which they aren't recommended. I've no idea what it is for asphalt shingles, but would be worth checking.

Your openings on the front are about as big as mine, as is your footprint, and the SE wanted the construction upping slightly to cope with the shear loads imposed at the upper plate. I know it's only a "shed" but would be worth getting some professional advice.

Even though I designed my Kingpost trusses\roof - I still had a SE run them thru for deflection\loads etc. and verify they'd hold up.

HIH

Dibs

 

[softtop]

Maybe I'm missing something but can't you use Velux windows in the roof? I've installed a few and they are easy to do and haven't leaked for me.

Didn't mean that you were lucky as in won the lottery - just I am envious of your design and space and especially the light! Everything I do I have to get permission from Conservation Officers (listed building) so my workshop is a dark hole...

I'll be watching this with interest.

 

[Cegidfa]

Hi Craig, thanks for the link. Whilst he made a sound job of the woodwork, I can hear Mike Garnham screaming....put the base up on brickwork to stop the rot. And as for the way the base was built...groundwork was not his forte. Yes, our build will be single storey and BTW I wish my mind was as tidy as the site.

Hi Dibs, the roof angles are, upper chord - 18.5°, lower chord - 60°. We just get away with the upper chord angle with respect to asphalt shingles. We did have a steeper upper angle
but it affects the balance between the two and looks disproportionate. It’s a tricky thing to get right when one is constrained to 4m in height.

Having seen commercially built gambrel sheds (in the USA , on the web) they use 4 x 2 for the whole construction and no collar ties, just relying on the gussets. Also, our conservatory is 4m square and that has one 10mm rod in the middle, and double glazing weighs far more than our proposed roof. From the experience at our last house we know that building regs are way over the top, to almost CYA levels (I could bore you, but I won’t). I remember Mike Garnham remonstrating with a shed builder who put one length of wire in the middle to hold it together and even he only suggested two more of the same, albeit better applied.
I do appreciate your concern though and thanks for that. It may well be that we will have to stiffen the roof if things start to move, especially with a overhang at each end. Preferably before it flies away :shock: .
As the build progresses I would appreciate your input if you see anything you think is a bit iffy. Nothing is fixed in stone, perhaps it should be round here

Reading your build, I came to the impression that you must be built like Garth, especially when you mentioned removing a c/h boiler that weighed 100kg, on your own. Could you please post us some muscles as you must have some to spare :lol:

Hi softtop, we could use Velux or Fakro but that would set us back the best part of £700 for three windows :shock: which is beyond our budget....that’s almost a table saw :wink:

As it happens, we do think that we have won the lottery, having moved from a middle terrace in Bromley to a detached house in rural Powys; so much for downsizing in retirement. What a shame you couldn’t have the design you wanted because of where you live, hopefully there are other compensations to living in a Conservation Area.

Regards....Dick.