Month: April 2013

LVL Beams

I finally got the beam on order (technically beams since there are nine pieces). Actually, I placed the order a week and a half ago. Given how long it’s taking to come in, I should have ordered it much sooner. I wound up ordering from Home Depot after checking with several different lumber yards. I ordered Weyerhauser Microllam, which is SFI Certified and classified as ultra low-emitting formaldehyde, the lowest possible for engineered wood. Microllam is a brand of LVL, or laminated veneer lumber, which is much stronger and stiffer than regular wood.

Things got more complicated when I started looking at brackets.The beam will be supported by a total of four columns that will be incorporated into the walls. Each of these columns will have both a “column cap” which is a metal bracket that connects the column to the beam, and a column base, which will be welded to the steel beam in the basement. The beam itself consists of three sections, each of which is three layers of 1 ¾” thick LVL, for a total of 5 ¼”. The columns are 3 ½” x 5 ¼” PSL (parallel strand lumber).

Column Cap

I spent a lot of time on Simpson Strong-Tie website reading specifications and learning about the different brackets, but I should have spent a bit more. After I ordered, I went back to the website to figure out what fasteners I needed to put it all together. First I noticed a note stating that for 5 ¼” LVL I should have ordered the 5 ½” bracket instead of the 5 ¼” bracket. I’m hoping it will still work because there’s a 15% restocking fee on special order returns and these brackets are more expensive than you’d expect. Then I discovered that the column caps I ordered require machine bolts that go all the way through the beam and columns, whereas if I had ordered the “Q” line, I could have used screws (albeit special “SDS” screws). I’d much prefer to use the screws, since they’d not only be easier to install but they won’t stick out from the surface of the bracket and complicate drywalling. For now I decided to hold off ordering the bolts, because if the brackets wind up not fitting I’ll return them and order the 5 ½” Q versions and use the SDS screws instead.

In addition to the column caps and the bolts (or screws) to connect them to the beams and columns, I need fasteners to connect the three layers of LVL beam together. I did some research and settled on Trusslok engineered wood screws, which are specifically designed for the purpose. The advantage over nails is that I only need about a quarter as many and can put them all in from one side. The other option was bolts, which (as I mentioned) make drywalling more difficult. I also tried ordering some low-VOC polyurethane adhesive to glue the beams together in addition to the screws (not necessary, but it would add additional strength), but the company wound up canceling my order. Since I’m now concerned about the beams fitting into the bracket I decided to skip the glue, since it has the potential to make the beams slightly thicker.

Once my order finally comes in I’ll need to schedule delivery from the store and then I’ll find out if the brackets will work. Given how expensive the LVL (and the hardware to install it) has wound up being, if I had it to do over I’d use steel. It would be a lower profile (stick down less from the ceiling) and not any more money.

Temporary wall

I’m getting behind on my blog updates! After my failed attempt to move the load bearing wall, I rounded up enough salvaged lumber to build a temporary wall. When I took down the temporary wall in the basement, I just knocked the sections of boards apart, leaving all of the nails in the sill and top plates. At the time it was simple laziness, but it paid off in spades because I was able to just line up the studs and pound the boards together with a hammer. Everything was already spaced roughly 16″ on center, so I just needed to find the matching top and bottom plates and then tilt up the sections and hammer them into place.

Between two walls

I put together about two thirds of the temporary wall, assembling each roughly four-foot section, tipping it up, and then pounding it into place with a sledge hammer. When I made the basement wall I carefully measured the distance from the floor to the underside of the joist and either shimmed or cut my studs down accordingly. This time I cut all the studs to the same length and just pounded on it until it was straight. It wasn’t as precise, but it went much more quickly. Everything is pretty snug without any really loose sections, so it worked out. Dean helped me put the last sections in place. The beam is on order (more about that in another post), so soon enough we can get that in.

The first floor has a single load bearing wall that runs the length of the house front to back. It divides the floor into roughly one-third/two-thirds, where the larger fraction was for the living room, dining room, bathroom, and kitchen while the smaller side was for bedrooms and the stairs. The house is relatively narrow: about twenty feet wide on the inside. This means the bedrooms were only a bit over seven feet wide, too small for anything other than a bathroom. As I was designing the new floor plan early last year it quickly became clear that in order to have an open concept we were going to need to get rid of the load bearing wall.

Load bearing wall

Because the wall is supporting the second floor we can’t simply remove it, we have to replace it with something of equal or greater strength. The plan calls for a 14″ LVL beam supported by two columns. The load bearing wall is directly over the beam in the basement that we recently upgraded to steel. The new columns and beam need to go in the same place in order to properly carry the structural load.

In the basement we built a temporary wall to support the floor while we removed the existing beam. For the first floor I got the idea of moving the load bearing wall over about 6″ to make room for the beam. To do this I would use the beam from the basement on jacks and posts to take the load off of a section of the wall, remove or cut any nails in the way and then tap the wall over one stud at a time, top and bottom, with a sledge hammer.

Beam and columns

I cut down the longest beam section into two nine-foot columns and the 16′ section as the beam. The beam weighs close to 150 lbs, so moving it was a bit of a hassle. I nailed the steel plates to the bottoms of the columns so that they wouldn’t fall out as they often did during the basement leveling. Since the house has ten foot ceilings, getting the beam into position was a bit of a challenge. Fortunately Sarah was able to help with the ladder and we got it in with minimal issues.

As a precaution, I put a jack post in the basement under the floor joist the bottle jack was sitting on. Then I pumped up the jacks until I heard some creaking from the ceiling joists. I spent a good hour prying flush nails out of the bottom plate, using a chisel and the edge of the hammer claw to scrape away the surface wood so I could get to them. Unfortunately, it became clear that the wall has been built by first nailing down the bottom plate and then standing up the studs and toe-nailing them in. That meant there were several places where the nails in the bottom plate were directly under studs. 

Anticipating this sort of problem I had picked up a corded reciprocating saw and some long blades, but putting it to use quickly disabused me of the notion. I simply couldn’t get at the nails under the studs without ripping things apart that I was trying to save. I didn’t even try to cut the nails in the top plate. The plan was not going to work.

One of the reasons I was trying to avoid building a temporary wall was I didn’t want to go buy lumber that I would only briefly need, but I got an idea. I counted the number of joists and then went down to the basement where we’d stacked all of the lumber we’d saved from demo. Sure enough, we had saved enough ten foot studs to build a temporary wall. I de-nailed the boards and stacked them up in preparation for the project. Now to figure out how to get that beam back down…