Monday, 9 June 2014

Wall Plate

Day 1: Monday. POOSHers =2 , Weather hot and sunny with possibility of thunder showers

We haven't quite finished wall-raising, but we have started on the wall plate and this week is going to be mostly about this phase of the build. The wall plate is a ring beam that sits on top of the final course of straw.

                     

And we spent a small part of the day on the wall plate. We glued and screwed the outer beams to the OSB bases. The wall plate is going to be in six sections, and each section is likely to be so heavy and awkward that it will take three of us to carry it. .

When we had it laid out on the ground on Friday, we marked up the exact location of each piece. So today, we were glueing one side of the beams, locating them on the OSB and clamping them, and then turning the assembly over and drilling then screwing through the OSB to pull the glued surfaces into tight contact.


 Six wall plate sections laid out. I have positioned the inner beams, and marked them up for fixing tomorrow.




But most of today was spent completing the fourth course of bales. These have been in place since Wednesday,  but before starting the fifth course we have checked and adjusted the position of all bales for alignment then driven 1350mm hazel stakes (two per bale) down through all four courses. It's been a day's work. You can't see the difference in the photographs, but I hope it will make a significant difference to the evenness of the walls at the finish.

Day 2. POOSHers = 3, Weather warm, dry and sunny.

We laid the fifth and final course of bales in a couple of hours this morning. It was the most straight-forward course of the five: no stakes to use, no window openings so fewer bales to customise. Better still, one of the part-bales we made last week was the perfect length to complete a wall section today.


 Not so much headroom on top of the wall


 Fifth course complete


Back to the wall plate this afternoon. We have been gluing and screwing the inner beams and noggins (spacers) to make it as strong and rigid as possible. 






If you look very closely at the mid-line of the OSB, you can see that we have also drilled 25mm holes here and there. These are for the final hazel stakes that will be driven down through the wall plate into the top courses of straw.

The wall platee - six finished sections back in the store and ready to put on top of the walls tomorrow.

Day 3. Wednesday. POOSHers = 3, Weather warm & dry

It's time to fit the wall plate, and the forecast is for dry weather. So - covers off...........


.......................sections up the scaffolding..........................


Position very carefully directly above the baseplate. Plumb lines, spirit levels, tape measures............



..................then drive in the small hazel stakes, through holes in the bottom boards.



                



Whoops! No photo of the lovely sheeps wool insulation . All voids were filled with 100mm thickness, then the wall plate top covers glued and screwed (or ring-nailed) into place.

Ready for compression tomorrow. 


and I'm hoping that when the straw either side of the window is compressed, the gap between the top course and the wall plate, over the window, will disappear.

Day 4 Thursday. POOSHers = 3, weather : warm, dry and sunny.

We have pre-compressed the straw today. We have worked our way around the walls with four steel bars and four heavy duty ratchet straps. If you look at the photos in "Wall-raising, Week1", you can see some lengths of blue water pipe running across the stem wall at regular intervals. These were marking some slots I had cut across the stem wall ready for this job. We push out the pipe with the steel rods - 20mm steel rebar cut to 600mm lengths - and pass the ratchet straps from one end of the bar up and over the wall plate then down to the other end. When you tighten the ratchet straps, you compress the straw wall between the base plate below and the wall plate above.

Before moving the straps along the wall one at a time, a length of (white) polyester pallet strap goes over the wall plate and under the base plate, tightened up with a monster parcel strapping tool (hired), and this strap is left in place, permanently. It will be plastered over.

Pictures follow, not necessarily in sequential order:








































So: this last photo shows what we have achieved today. We have reduced the height of the walls by around 5 cm! The top of the wall plate was level with the black line on the post before we started.

But, by compressing the walls there has been a much more significant change in the strength and stability of the walls. They feel sturdy and steady enough to build a roof on. However, everyone has been working hard for four days, and we have reached a suitable point to take a break, so today was the last day of work this week.


Tuesday, 3 June 2014

Wall Raising Week 2

Day 1: Monday 2nd June.

POOSHers = 2, Friends = 1. Weather: dry and sunny, rain forecast later (which did not materialise)



And we start week 2 where I left off on Friday - putting hazel stubbies into the base plate and fitting the first course of bales as carefully and as straight as we can. New POOSHers Laura and Jam are here for two weeks, and there are likely to be quite a lot of photos of them.



After completing the first course, the second course is relatively straight-forward bale laying. If I had known my average bale length at the design stage, I would be forging ahead with just the occasional half-bale to make. However, with the slightly shorter-than-expected bales I have bought, a bale needs to be shortened for each of the wall segments, which is five per course (because of the door opening); six on course two (window opening) and seven on courses three and four (two window openings). So most of the day is spent adjusting bale lengths.


Large window box in position sitting on the first course of bales. The box is pinned through the bottom into the bales it is resting on.


Second course nearing completion. We have moved some more bales down from the shelter for tomorrow.

Day 2: Tuesday. Two POOSHers. Weather: warm, cloudy, occasional drizzle

Another day, another course of bales. This is quite a relaxed pace of work for three people. There are bales to dress, careful positioning, bale length adjustments, positioning and pinning of the second window.



We had a "make your own persuader" session first thing, to get ready for bale staking when we reach the fourth course. Logs from the wood store, hazel from the leftover hazel pile.


Small window box, inverted, with its bottom stakes showing. The box is stuffed with sheep fleece insulation.


And this is the end of the day, with the third course completed. Stack of bales in the centre ready for tomorrow, some split bales in the the window box. The wall is getting higher to work on now. We have the scaffold outside, but may not be able to work from it tomorrow because there is rain forecast.

Bale customising with ratchet straps:




I have been experimenting with using a ratchet strap to help compress bales when splitting them. We are putting new bale twine around the bale sections in the conventional manner with a bale needle, but before we tie the strings with a pulley system of hitches, we are using the ratchet strap to compress the bale between two boards.


The string I am holding above is the original bale string which was extremely tight and now has quite a lot of slack in it. Next, you tie up the four new strings (without having to strain to make them as tight as possible), cut the original strings and release the ratchet strap. The straw expands to make a couple of tight bale sections.


We found it was best to have the ratchet on the end of the bale where a board is. If you have it along one side, you get higher tension there than on the other side, and your bale goes all trapezoid. 

Day 3 Wednesday. POOSHers = 2, from other networks = 1. Weather: Rain

Rain on and off all day, so inside work under the covers. We have completed the fourth course, "persuaded"  the long back wall into the straightest shape we can manage, and staked the first four courses of the back wall will hazel.

We have also stacked sufficient bales to finish the fifth course ready under the building covers. This is a relief, as I had some water leak into the top of my bale stack, and i suspected that it might have penetrated down to the bottom of the stack, but haven't been able to assess the loss until now. I bought around 18 bales more than I needed for contingencies and because of the pack size, and I have water damage to around 14 of them.


Straightened out with a little persuasion

Laura - Straw-lover
So: just looking at the window in the background of this picture: I think I got the height of the window about right. The straw is about 40 or 50 mm above the top of the window box, but after pre-compressing the straw, the box top should be level with the top of course four. The other window doesn't look as well-judged at present.


First stake

High stakes



More stakes

Day 4 Friday. POOSHers = 2, Weather warm, dry and sunny.

Thursday was a rest day, so Friday is the fourth and final day of week 2. And it is also the first dry day of the week, so a good opportunity to do some outdoor work. We are going to start making the wall plate, which will sit on top of the final course of bales.

First job: measure the base plate under the bales (again!). The wall plate should be the same size. Then we laid out a rectangle of this size on the grass with fencing pins and bale twine and measured the diagonals to make sure it was a perfect rectangle.


If you read this blog in March, you might have seen that I cut all the OSB for the wall plate in advance. Laid out on the grass today, it was a pretty good fit - it just needed a few millimetres taken of here and there. We laid out, measured and cut 4 x 2 timber on the the OSB for the outer beam.


Cutting noggins with a chop saw. The saw is fixed to the bench, and I have made an end-stop for the timber so we could cut off 350mm lengths without measuring each one


                            


Inner beams cut to length. It is not essential to do overlapping joints, but it's cosmetically very pleasing.


This took the whole day. We'll start next week gluing and screwing the beams to the OSB in six sections, ready for final assembly on top of the straw.