Friday, February 18, 2011

I just do not feel supported.

The exterior shell is now a completed structure, house wrapped and windows installed. Much thanks to my brothers and Mr Gbr for the help in getting the house wrap on. It was great fun monkeying around on the scaffolding 30 feet above the rocky bottom.
Now I am plugging away at the interior walls and structure. For the last several weeks I have been doing my best to ensure that the beams will be level, the walls moderately perpendicular, and nothing majorly damaged. You may have noted in a previous posting my concerns with what is considered abnormal joist framing, but my notes today center around the stairs to the basement.

The basement is an interesting scenario, we ended up replacing the whole foundation and while I am very glad that we did there have been some technical issues resulting. One of these issues is that the stairs going to the basement, in addition to being ripped out with the old foundation, do not have the required headroom and do not have enough length to accommodate a straight run before running into the exterior wall. My solution is that I am making a U-shaped stair. However, as the landing occurs prior to having enough depth for the required headroom I am forced to have a segment of floor aprox 16" higher than the main floor. I doubt that this would be a major issue, except that the stair walls are both load bearing and I must shorten one.
I am not able to do walls from the basement floor as I have not had one poured yet so I am using a triple 2x8 load bearing beam and using the assumption that I will not have any support under it. While not true in the end, it will be until I have a basement floor. The ends are supported at the foundation wall and also on one of the two main steel beam girders. All of this to say I rebuilt the wall after placing a temp support which would hold the load of the second floor bathroom and the ceiling. The temp support was jacked to a position 1/32" above my desired final wall height. (My philosophy is using the "least change poss") After building the wall I removed the support beam and jacks, the wall came down 1/64th and hoovered there. I had to go up top practice my awesome dance moves in order to get it to make physical contact with the new "load bearing wall". I find it rather amazing that a floor and ceiling would just "hang out" only being supported by one side but as they say old wood has found itself a set position and just does not like to move. It is now well secured and up to current codes (ish).

A bridge to nowhere.

Those filthy politicians are doing it all the time and desiring to get into politics someday I thought that I might join in the fun. What fun you might ask, well, building a nearly useless bridge of course.
In my attempt to throw money at everything that either moves or is nailed down I just purchased a large pile of lumber which should be delivered sometime next Friday. While other people may enjoy the idea of hauling 30 sheets of 3/4" plywood up and down the muddy embankment that is the front yard, I do not. It was my original intent to build a small "normal" front porch, followed by a bridge to the sidewalk, however, I am not planning on building the porch for a while. Now is a good time for building a bridge that I can cut to size when the time comes. I doubt that I will be able to do so, but if I can convince the Inspector to buy off on only having a bridge than I will opt to not build the porch and recover the structure with plank instead of plywood.

The construction is simple enough. Four sixteen foot 2x8's, some solid cross bracing, covered with a couple of sheets 3/4" treated plywood. For the supports I took some 4x4's and made a center support. The two ends are supported one on the ground and the other sitting on the old cast cement stairs. There are a couple of additional pcs bracing to keep the whole structure very stable. Before commencing on such an endeavor I would recommend conversing with your local building inspector. I did not in this case as I have a occupancy permit out and do not intend on leaving the bridge in its current configuration as a final design.
One thing that is a good idea on anything that will be subjected to dynamic loads is to build in some overkill. In this case I like to refer to an easy to use span chart as the start of my design, such as this one from AWC. Noting 2x6 16" OC, exterior and the species I am using: I could span greater than 8 ft with a 50Live,15dead load. So using 2x8 ft is reasonable overkill. The whole of the structure floats and is not connected to the house, for this reason it is important to have the supports well braced as shown. Also side loaded movement is minimized by using plywood and having a small cross brace on the center support. I should mention that all the lumber I am using on this bridge is coming from my culled lumber pile which I purchased about 6 months ago, mainly 2x4 and 2x8 ish treated lumber in the 16 plus foot range usually having a twist or split at an end. I purchased the whole of the pile for under $200 and have been using it ever since. I am thankful that God has helped me in finding some good sale items as I as yet have not found a corporate sponsor.
I will likely throw on some basic rails after getting the lumber inside. If I am able to make it permanent I will likely be forced into using footings for the support, but we shall cross that bridge when it arrives.