So quite a bit has happened since the last update. I will make an attempt to go through everything that has happened.
As soon as the concrete contractor was done we moved in to start preparing for the concrete floor. This would involve installing interior perimeter drains, conduits for electrical service as well as telephone and cable TV. With this installed we would place some gravel and then top it off with a finer material to provide a smooth surface. On top of this goes a vapour barrier and finally insulation.
We started in the morning with a big pile of white 4″ perforated PVC pipe. This was laid down along the interior of the concrete footings. The purpose of these pipes are to collect any water that might come inside and below the house. For this purpose they have holes along the bottom through which the water might enter. It is not strictly necessary to run perimeter drains on the inside of your foundation. However we made this choice because the ground we sit on it solid and water does not drain through it at all. This way if water does get below the house it will have a way to drain out.
Because we are going with an underground electrical service we need a way to get the main power cable into the house. This can be done either by burying an armoured cable, or providing conduits to pull cables through.
We were very careful in the placement of this conduit as it was supposed to come up right the middle of a wall.
The grey conduit in the picture is for the electrical cable. It is an extra thick type of PVC pipe. Quite expensive and so are the fittings.
Similar requirements exist for the telephone and cable company. In our case we have provided separate conduits for the cable and telephone service. They are the smaller orange pipes.
Unfortunately the contractor placed the sleeves in the concrete in the reverse order, so we had to “snake” the grey and orange pipes around each other rather.
For a quick laugh about the sleeves. I neglected to put couplings on the ends of my conduit sleeves. So when the concrete forms came off everything was flush with the wall as expected only there was no way to slip the couplings over the pipes.
This oversight would require me to chisel out the concrete an inch deep around the three sleeves. After doing about a third of it by hand for an hour I rented a hammerdrill the next day and had it done in 20 minutes.
At the same time our plumber came out and started his underslab rough-ins. We put in two waterlines. One that we will use and a spare in case something happens to the first one. They also installed all the sewer lines that will run beneath the floor.
With the pipes and conduits in place we called for a truckload of gravel. We used a so-called “slinger truck” which is a truck with a conveyor belt on the rear. Using this conveyor belt the operator can shoot gravel up to 30 feet with high precision. This takes away alot of manual work to get the gravel where it needs to.
We added a minimum of 12″ of gravel throughout the foundation. The gravel serves as a permeable layer that water can flow through, to the drain pipes. It also provides a capillary break, preventing water from wicking up through it as might happen with other, more sandy materials.
On top of the gravel we placed a layer of filter fabric. This is to keep the top layer, which will contain a mixture of fine grain particles and gravel from mixing with the gravel, keeping it clean and free draining.
With the fabric laid down we called for the slinger truck again, this time with a load of screened pit run. This is a mixture of gravel and sand with no rocks larger than 2″. When we compact it with a plate compactor it forms a very hard and smooth base for the next stage.
We knew that there was rain in the forecast and we need to keep going to finish the foundation. Because we were about to lay down plastic vapour barrier and insulation it would keep any rainfall from draining out. It would get trapped between the layers and we neede to keep any water out of it.
To this purpose we purchased the largest tarp they had at the store. Trying to wrap exposed concrete walls, with sharp corners, stepped edges and exposed anchor bolts turned out to be a challenge.
With some leftover lumber we screwed together a sort of space frame to hold up the tarp while we worked on the inside. Something that we learned along the way was, if you think you have the tarpe tied down enough, you don’t. If the supports seem sturdy enough, they probably aren’t.
While we were waiting for better weather the tarp came down twice. The day we were hoping to have our floor slab poured we had to spend a whole day tearing up the insulation in sections and vacuuming out standing water trapped on top of the vapour barrier.
The day after that we could finally, after many delays have our floor slab poured. The weather was nice and the truck arrived at 9 o’clock sharp.
There was a crew of five. Two guys going back and forth with wheelbarrows moving concrete from the truck to wherever it needed to be while the three others were raking, screeding and checking levels.
Getting the concrete in took about 3 hours. Then half of the crew left and the two remainding members used machines to finish the floor. I did not get any pictures of them as I had left at this point.
That will be the last we see of the concrete truck until it is time to build the carport.
With the concrete setting I was ready to inform the people I have hired for the assembly work that they could get started.
I was very careful in picking who we used for this part and we ended up with someone who has done quite a bit of work out on Ship’s Point.
The floor slab was poured on Tuesday Jan 31st and they started the very next day.
By the time I arrived at around lunchtime, they had removed the rickety tarp supports and were moving the lower floor wall panels in place.
The North side with the bedroom window opening at the stepped concrete wall.
The bedroom window is an example of what might happen if, during the review process of the prefab drawings, you mistake your wording.
During the design you need to check all the drawings against each other to make sure that everything lines up properly. In this case it involves the architectural drawings that the dimension of the foundation derive from. On top of that I need to reconcile them with drawings from Insulspan as well as Pacific Building Systems. In this case I noted that the “bottom of sill” of the wall panel framing the window be at 4’9-1/2″ to concide with a concrete wall of 4′-8″ with a 1 1/2″ sill plate sitting on it. But I said “bottom of sill”, when it should have said “TOP of sill”. This means the wall panel window starts 1 1/2″ higher than the wall. It is no big deal to add some extra wood afterwards to bring everything in line, but it is added work and materials that should not have been there and it highlights the importance of drawing review and terminology.
The wall panels come complete with pressure treated sill plates. The guys added extra sill gasket to the bottom of the walls. Not strictly necessary, but good for the longevity and a nice touch.
At the end of Friday they had installed all the lower floor walls, the floor joists and started on the sheathing.
The joists are pink because they are painted with a coating that is mold and fire resistant.
This is where we are sitting now. On Monday they will work as far as they can go before things need to start to tie in with the SIPs panels, which are scheduled to arrive on Tuesday.