Jump to content

More foundation fun - straw bale garden room on clay


Nick Thomas

Recommended Posts

I'm having a break from the lime render before starting the next coat. Decided to convert a bunch of offcuts from the ceiling and floor into a unit running the length of the round window wall. I can screw it to the floor joists and render right up to it, to make it integrated AF. Leaving the render behind it just basecoated will save me some too.

 

I had to buy some 2x1 and 2x2 to make a frame to hang everything off, and all I could get on a Saturday afternoon was rough-sawn from b&q, so I got to play with an electric planer too.

 

box.thumb.jpg.53f27832b4b2564aa5f1fcadc59d04c8.jpg

 

Progress so far... well... it's a pine box ^^. Don't stand on it yet. I'm planning to divide it into three compartments with panels made out of planks surrounded by 2x1, which will make it a bit sturdier. The perimeter is all 2x2. I was going to have a go at mortise and tenon joints, but chickened out and am just using lots of glue and pocket screws.

 

I guess I'll need trim pieces on the front, and some jiggery-pokery to get the wood closer to the lime. The sink will be in the corner closest to the door - probably a counter-top one, to minimise holes through the worktop, with a couple more bits of 2x2 to support it underneath. Then a couple of sockets in each of the other compartments. Cables and pipes will come through from the back.

 

Doors? I guess? They'll have to be flush with the trim, the floorboard offcuts being used for the worktop aren't long enough to give me a decent overhang ^^. Each compartment will be about 7000mm wide at the front, so 2x 350mm doors? I don't have any wood for them yet.

 

I need wood for shelves too. I've got some old decking boards that were going to be the floor; maybe they'd look alright, planed up a bit.

Link to comment
Share on other sites

Posted (edited)

OK, unit finished except for shelves, doors and trim. Sink is arriving tomorrow, so I get to start fitting services soon. I figure I'll make them all temporary and pluggable until I can dig a trench and get a Real Electrician™ out for that side of things.

 

IMG_20240706_195857.thumb.jpg.54813532092d5240209b14d79fad34af.jpgIMG_20240706_215237.thumb.jpg.8b48470dd1de55b3deda6796f63ff200.jpg

 

Got a second coat on the east wall, and it's looking much better than I expected it to. It still undulates, but most of the smaller-scale variation is just... gone. Trowelling it on is much harder and slower than slapping it on with my hands though ^^. One bag went pretty far; the remaining seven ought to be enough to finish this coat everywhere, but I'll definitely need more for the final coat.

 

IMG_20240708_220712.thumb.jpg.10adb234f12dc5cfd5bfb86098f73b2d.jpg

 

 

Edited by Nick Thomas
  • Like 3
Link to comment
Share on other sites

Another bag down. Managed to destroy my foot somehow doing this, so I'm out of action for a bit now. Tendonitis or something? From going up and down the ladder in stupid shoes? Sigh.

 

IMG_20240712_113216.thumb.jpg.7150994e647329e2024c9487a94dc662.jpg

 

 

Link to comment
Share on other sites

  • 2 weeks later...

Back in action. Finished the second coat outside, and got started on the inside today.

 

IMG_20240719_175738.thumb.jpg.9887279b470d6cc503ec74a893ef7964.jpgIMG_20240722_211010.thumb.jpg.5af11d471eabe2bca9b7fb0c4c4357bd.jpg

 

Three bags of lime left, but I'm out of sand. I can either get as much as I need in 25kg bags for ~£50, or get another whole bulk bag for ~£60. I'm very slightly short of all sorts of things right now, which is a bit of a pain.

 

I did clean the lime off the bubble window ^^.

  • Like 1
Link to comment
Share on other sites

On 13/07/2024 at 13:29, Nick Thomas said:

From going up and down the ladder in stupid shoes? Sigh.

ladders  are not for  that job  and cotinuops working at height and reaching out on--use a hop-up or small scaffolding 

it will be bettter ,safwer and probably quicker in the long run

Iknow about pains being an old age builder 

and first thing is proper work boots 

easy to end up with a life long  problem iif your not careful

Edited by scottishjohn
  • Thanks 1
Link to comment
Share on other sites

Honestly I'm a bit of a health & safety nightmare at the best of times. But yeah, after that I got a little step-up for the inside and will be getting a big one for the outside. I've got some lovely work boots, I'm just stupid enough to wear slippers instead sometimes 🙄.

 

Second coat is finished now, aside from a couple of spots where there were really deep voids to fill - I decided not to try to turn them into niches, in favour of just filling them up with copious amounts of straw-lime.

 

image_2024-07-25_14-48-42.thumb.jpg.9b198c70c0d61a0128e9b35571d08d18.jpgimage_2024-07-28_21-25-50.thumb.jpg.5630f256ec0a62bb0b71788daa99dbd1.jpgimage_2024-07-29_16-15-20.thumb.jpg.0c98966f3ded124202ca692a1c94207c.jpg

 

I probably need one more bag of NHL3.5 to finish the voids off, then enough NHL2 to do the finish coat with fine plastering sand over the lot. Calculators suggest that could be another 400-800kg of render at 2.5:1 - another 9 bags of lime in the worst case (~10mm thick), 5 if I go for 6mm thick. I think I'd have ended up using significantly less lime if I'd gone the stipple coat route, but, oh well. Some of the void filling has been ridiculous as well ^^.

 

I still need to fit the services, and of course, I've made life difficult for myself there by plastering the unit in. I figure I can cut a series of portholes for access and make them reopenable though. Something to do while taking a breather and collecting the materials for the final coat.

 

I feel like I'm getting better at plastering, but it'll be interesting to see if I can manage a decent level of finish for this final coat. Top rule has to be "don't stop halfway through an elevation" ^^. I looked into buying premixed bags of lime topcoat to control consumption a bit better, but first impression is that it's wildly overpriced.

Link to comment
Share on other sites

2 minutes ago, Gus Potter said:

Have you worked out what it has cost you to date?

 

I've kept a spreadsheet ^^. Ignoring tools, the unit, services, things I bought but never used, and factoring in what I'll need for the finish coat, I'm at about £4500, making the straw less than 10% of the total build cost.

 

Other big-ticket categories - about a quarter was wood: OSB, 2x4, 2x6, 2x8, floorboards, ceiling cladding, that kind of thing. I was buying a lot of that piecemeal, due to limited storage, so I also paid a fair bit out for delivery, and used what I had fairly inefficiently. Could probably get this down a fair bit with better planning.

 

I already had the doors, but spent ~£500 on windows-that-got-used. Honestly, I'm not very happy with the doors, but won't think about a replacement until after everything else is done. Might be another £1000-2000 if I went for something with a big double-glazed panel on the side - it's a ~1.3M wide gap that needs filling.

 

It's taken a long time, but I've not actually put a huge number of labour hours into it. I've not tracked that closely, but the rendering has been ~20x6hr sessions so far, for instance. At £25/hr that'd be a nominal £3K. Doing load-bearing straw like this swaps out a lot of technological wizardry in favour of brute-force labour like that ^^. If I were to do it again, especially at a larger scale, I'd probably be thinking about straw SIP stuff instead, and it seems like the direction of travel is generally that way. I found https://www.thelaststraw.org/panel-fever/ a very interesting read on that front.

  • Like 1
Link to comment
Share on other sites

  • 3 weeks later...

This is actually working \o/

 

finish-coat-1.thumb.jpg.7780428e11f0d4017f0179e7511a5331.jpg

 

(Right hand side is rubbed up, left hand side is not). Managed to get two bags on in one day yesterday, right the way up to the door at the front. The finer sand really aids workability, although it's not *great* stuff, there are some big pebbles in it, and a little bit of sharp glass. Found some charcoal as well? Still, 3 more long days of this and I should be finished.

 

A few hairline cracks have shown up, especially in the very first section, where I think I put it on a bit thick. So far they've all rubbed out without issue. Limewash apparently helps to heal them as well, once it's time for that. Or I can always cut bits out and re-do, but hopefully it won't come to that.

 

Still not level, obviously.

  • Like 1
Link to comment
Share on other sites

Posted (edited)

final-coat-2.thumb.jpg.fce563dff31fe9d750f06f16b852fd1f.jpgfinal-coat-3.thumb.jpg.9fb1a4ea9125a612b9fa3c316a605ac5.jpgfinal-coat-4.thumb.jpg.430a7752def72dc8a121a1a9c327801b.jpg

 

Got there in the end. A break from rendering to let the hands heal from lime burns (d'oh) is in order before the final coat inside. Plenty of other stuff to do though.

 

It's going to be great to take the hessian down in a week or so, although I've got one awkward set of neighbours who have already telegraphed that they're going to hate it (and hate everything already done; and hate that I replaced a rotten pergola with a huge viney beast straddling it with a modest building). They've been out measuring, bless 'em, but it's definitely <2.5M. Fortunately, the other neighbours range from indifferent to fascinated.

 

I offered some evergreen screening as an option to block their view of the side a while back; trying to work out what's most cost-effective (and would be happy in pots) there. 2.5M tall trees, even bamboo, doesn't come cheap 😬

Edited by Nick Thomas
  • Like 1
Link to comment
Share on other sites

On 15/08/2024 at 23:15, Nick Thomas said:

have already telegraphed that they're going to hate it (and hate everything already done;

 

On 15/08/2024 at 23:15, Nick Thomas said:

offered some evergreen screening as an option to block their view

Don’t bother, neighbours like this are never satisfied, stuff them, it looks good, well done 👍

  • Thanks 1
Link to comment
Share on other sites

Managed to injure myself down at the allotment, so a bit delayed on the plastering indoors. Just finished now; it took 3 bags of lime and all the sand I had left. Phew. Now for a week of checking it several times a day for cracking.

 

Once it's had some time to cure, it'll get painted. I'm thinking whiteish silicate paint outside and earthborn "claypaint" inside - they have an offensively yellow shade which is reminiscent of the straw. Dunno if either will hide hairline cracks, or if I'll need to do something about any that show up first.

 

I still need to get doors on the unit, shelves in, oil all the wood and fit the services too, but that's everything that could be called construction finished.

 

Thanks everyone who made suggestions, checked my maths, or just offered encouragement. It's been a great help throughout!

 

IMG_20240829_163608.thumb.jpg.556b3283f288ebbdd9ea49bd09b7ef86.jpgIMG_20240829_160742.thumb.jpg.c4620918996e9794180118ea635b54d1.jpgIMG_20240829_163557.thumb.jpg.1c01b4a9e26e67610df119025b210903.jpg

Link to comment
Share on other sites

  • 2 weeks later...
  • 3 weeks later...

And the inside painted. So nice to wave goodbye to that horrible grey.

 

painted-east.thumb.jpg.bda172c77be4e08d26001d043089387a.jpgpainted-north.thumb.jpg.c34c8f2a6159f26d73c52e23ac083b0a.jpgpainted-west.thumb.jpg.cdb2e9cda69f1f92abe424c613971456.jpg

 

It needed to be vapour-permeable, and I went through a bunch of options. Ended up using "Farnovo", which comes as a powder you add water and pigment to - https://dpm-mashel.de/en/wandfarbe-farnovo.php. One 5kg bag + 40g "rusty sun" pigment was enough to do two coats with plenty left over - ~20sqm per coat - and it has hidden all manner of sins. That top coat of plaster ended up cracking a fair bit as it dried, but good luck spotting any. Expensive stuff though.

 

I looked at earthborn "claypaint" which comes wet, but they add some preservatives to it which seemed unnecessary and allergenic to boot. The mixing is very easy, I might go this way for painting inside the house too ^^.

 

I've also run some 4mm² SWA in conduit between garden room and garage - it's about 25M, going under the garden room, then the decking, then along a fence - but I've left it there for now and am poking electricians for quotes. Seems I can't just do it as a spur since it's an outbuilding - it needs to go from the consumer unit as its own circuit? Grumble grumble.

  • Like 1
Link to comment
Share on other sites

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...