A very busy day, the first delivery of bricks and multiple visits from neighbours.
I am having the bricks delivered now to get them into the back garden where they will be out of the way. I have also been told that because of the mini-boom in house building bricks are on long lead times. Drama when he tried to drive down the ramp into the back garden. Because of the recent rain the chalk has become slippery and the lorry started to slide sideways! The pump arrived and so the 4″ of water in the bottom of the basement has now been pumped out.
Meanwhile, Tom managed to sever the mains electricity supply to the house with his digger bucket while back filling the hole. Southern electric were out quickly and repaired the supply in the rain without isolating the house! The man worked on the live cable wearing a thick pair of marigolds!! This means Tom has now cut off all three utilities – Water, Gas and electric.
The back fill has now been competed to the top of the insulation which makes the site look much more tidy.
Interesting developments on the neighbours front. Three visited the site today. One to add her voice to the original complaint about the garden and two others who were much more encouraging about what is going on. One of my “supporters” has asked me down for coffee and cakes on Friday at 10.00 am when all of the neighbours will be there. A good opportunity to calm troubled waters.
With lots of chalk scraped off the garden for back fill, we are hopefully already addressing the major issue. Watch this space.
With heavy rain over the Easter weekend , we returned to work on Tuesday to find a couple of inches of water in the new basement. As it is built of waterproof concrete there is nowhere for it to go. Not surprising really. Next job buy a pump to get it out.
Until it arrives work continued outside to remove the shuttering.
With the walls exposed work started to attach the insulation prior to back-filling.
Following a complaint from a neighbour, a planning enforcement officer visited the site yesterday. The issue, as I understand it, is the condition of my garden.
The officer talked to Tom as I wasn’t there and took a number of photographs. He is yet to contact me directly. This is clearly of great concern to me as I don’t want to break any laws. The site is kept tidy and the garden will be returned to its original use once work is complete. At this stage however it is a building site.
Tom has started backfilling the lowest level of the walls just reduce the amount of spoil on site.
A stressful time until I get the officer’s report!
This week work began in earnest to form the wooden shuttering into which he wall concrete will be poured.
The shuttering is a simple design to produce a reinforced concrete wall without the possibility of cold bridging, To insure it is straight and vertical, braced props are made from lengths of 4*2 timber.
Scaffold planks are then laid against the internal face of the uprights. Between the first and second planks and above the sixth plank resin rods a inserted through the wall.
Either side of these resin rods (steel ones would conduct heat through he wall). Large 6 inch timbers are placed either side of the rod and clamped in place with a steel plate and large resin nut.
Inside the wall the width of the wall is determined by small resin nuts set on the resin rod the correct distance apart.
Finally, planks are placed on the exterior surface of the wall and more strong boys bolted into place to provide rigidity for the whole structure.
Once all of the shuttering was in place scaffolders came to build a platform inside the shuttering which can be used when pouring and vibrating the concrete.
The concrete floor was left overnight and the next day work started on the walls. Firstly the area around the reinforcing rods which are the start of the walls was “scabbled” with a pneumatic tool. This removes the surface of the concrete leaving the aggregate stones showing and provides a clean surface to which the wall concrete can adhere.
Large panels of steel mesh are then cut to size and attached to the upright bars poking through the concrete floor. “U” shape pieces of rebar are tied to the two layers of mesh to keep them the correct distance apart. Finally “L” shape rebars are attached to the corners of the structure whilst the walls are tested for vertical position.
Once the corners are tied together the entire structure is very rigid and completely self supporting. At the end of the fifth week nearly all of the wall steel is in place and tied. The next step is to build the wooden shuttering around the steel mesh into which the concrete will be poured.
Can you see the hole cut in the mesh in the picture below? This will form a window opening in the basement which will allow natural light to flood into some of the basement rooms.
The concrete pour for the lower section of the walls is provisionally booked for next Friday 11th April. Let us hope that it goes more smoothly than the floor pour!
I had to coordinate a number of groups of people and activities to get this to happen – Tom and his boys, Phil the concrete expert, the concrete pump and delivery of 33 cubic metres of concrete. Everything was due to start at 8 am.
Shaylor’s concrete pump was there at 07.30 ( but it did only have to come from Greenland’s farm – a mile at most). Then the message came that the first of 5 RMC lorries were on their way. Phil, Tom and the boys were all stuck in traffic. The concrete only has a two hour shelf life and had to come the long way round because of the weak bridge at Pangbourne.
After much nail biting the first lorry arrived and Phil added the waterproofing chemicals. But the mix was very dry and the pump operator was not keen to put it through his pump in case it stuck and set solid.
A small amount of water was added and it pumped successfully although it was very stiff and hard for the boys to manoeuvre.
The second lorry arrived and things started to go smoothly – then near disaster. The third lorry didnt arrive and an hour later we were still waiting. The pump had to be washed out to prevent damage and a lot of angry words were exchanged.
Eventually all the concrete came and the basement floor was finished at about 1.30. A lot of clearing up and then everyone disappeared to leave the concrete to dry.
With the insulation covered by a water proof membrane and 50 cms of concrete the boys now had a firm base on which to work. They started by laying “Mars bars” (Spacers below the steel to allow the concrete to flow under the mesh). Then they placed “Armchairs” on the bottom layer of steel to support the top layer of steel with the correct spacing between the reinforcing sheets.
All of the steel reinforcing is tied together with steel wire. In this case 150 mm long double loop ties, twisted with a special tool to save the boys wrists. With the two layers of steel mesh correctly positioned and tied together works started to add the “L bars” which form the starters for the walls.
At this stage there was a final check on the location of the starter bars to make sure the walls of the basement are in exactly the correct place. The timber frame will be fitting directly on top of these basement walls and so they have to be just right otherwise there will be some costly changes when the timber frame arrives!
The shuttering has been built for the basement slab which is the very base of the house. Within this is fitted the special insulation and eventually the waterproof concrete will be poured up to the the top of the shuttering
With the base flat Tom & James start to lay two layers of 60mm Styrodur insulation. This is a special non-compressible form of expanded polysyrene which is laid as overlapping waterproof boards.
With all the Styrodur in place we are ready for the waterproof membrane which will be laid just before a 50 mm layer of concrete is poured to form a firm base onto which the reinforced concrete slab can be built.
Eventually more Styrodur will be attached to the walls of the basement so that it sits in a warm envelope which will encapsulate the whole house. This is a key element of the energy saving design.
At the start of week 3 the building really starts – rather than the destruction up to this point. The bottom of the hole has been blinded with sharp sand and is now completely flat and level at the the required height.
The steel lorry arrives
The reinforcing steel has been delivered (Approximately 7 tons of steel mesh and rebar).
The construction of the shuttering for the basement floor slab is underway.