|Home | Wiring | Plumbing | Kitchen/Bath
All that now remains is the wood framing. Having al ready examined the structural framework , you should start by removing the partition walls.
Taking out a nonbearing wall is relatively simple. Begin by taking out the studs. The proper technique for this depends on two factors: how the studs are nailed to the plates and whether you plan to save them. To remove the studs in one piece takes more time, but you may decide it’s worth it. (See earlier discussion on salvaging materials.)
If the studs are end-nailed through the top plate and toe-nailed to the sole plate, use a nail puller or wrecking bar to pull out the toenails. Once the lower end is free, grasp the stud in the middle and twist and pry it loose from the top plate. Be careful not to damage any ceiling surfaces you want to save.
If the studs are end-nailed to both top and sole plates, it may be impossible to remove them without damage. You can try pounding the base of the stud with a maul, but this often results in breaking or splintering the wood. Or you can use a reciprocating saw with a utility blade and cut through both wood and nails at the base of the stud.
If you choose not to save the studs, smash them out with a maul. Or you can cut them in half with a reciprocating or circular saw. (Be careful of saw kickback as you finish your cut.) Then twist and pry out both ends. Be sure to remove or flatten any protruding nails once the studs are down.
Alter the studs are out, remove the top and sole plates. If the ends of the plates are tied into the sidewalls. cut them off flush. Then use a wrecking bar to pry one end free. Again take care not to damage any floor or ceiling surfaces you want to save. To keep the bar from gouging the surfaces, use a wood block wrapped in cloth behind the head. If you can’t pry the plates with this method, cut out several inches in the center of the plate with a wood chisel or reciprocating saw. Use this gap to get beneath the plate with a wrecking bar and pry out both ends.
As with nonbearing walls, begin by stripping the surface material and removing the existing utilities. Removing the finish material doesn’t affect the structure of the wall. As long as you don’t cut or damage any of the framing. the structural capacity of the wall is intact. Once the framing is exposed, remove all debris from the area.
At this point there are two new factors to consider. One is installing a permanent support beam to carry the load once the wall has been removed. The other is erecting any temporary supports necessary while the work is in progress (see below).
To install a permanent beam to replace the bearing wall, you have two options. The first type of beam is a strongback, which is built in the attic and remains out of sight. The existing ceiling joists are suspended from the beam with metal joist hangers. For this installation you need access to the attic area immediately above the bearing wall, plus sufficient working space. No temporary supports are necessary because the beam is in stalled before the wall is torn down.
If there is no attic access, or if there is another story above, you must choose the second option—the ex posed beam. This type of beam supports the joists from underneath and is visible in the room. The bottom of the beam should be at least 6 feet 8 inches from the floor to provide sufficient headroom. Temporary supports must be installed before the wall can be torn out.
To install an attic beam, begin by drilling two small holes through the ceiling surface at each end of the bearing wall. From the attic locate the holes and the position of the wall. If there is no subfloor in the attic, put down enough planks or ½-inch plywood so you can work safely. If the space between joists is filled with loose insulation, use two long wires to probe through the ceiling holes. If there are insulating balls or blankets in place. pull them back before probing.
Measure the length of wall being demolished. The proper size of the replacement beam is determined by the length of this span, including bearing points. You can use various span charts for this information, but your best bet is to check the local building code. Call the building department or consult your copy of the code for the correct beam size. Position the ends of the beam so they are directly over studs for carrying the load. You may have to install posts for support.
Generally the new beam must be a 4 by 8, 4 by 10, or 4 by 12. In many instances it doesn’t have to be solid lumber. Two pieces of 2-by lumber can be used to fabricate a built-up beam; some codes require three. If you have limited access to the attic and can’t get long lengths into the space, build a beam from shorter pieces of 2-by lumber. Nail three widths together with 16d nails staggered every 12 inches or so. Also stagger the joints to achieve the necessary beam length. This is the structural equivalent of solid 4-by lumber.
Position the new beam over the joists and toenail the ends to the outside joists. A 3- to 4-foot 2 by 6 nailed to each end of the beam will distribute its weight along these outside joists. Also be sure there is sufficient bearing under the two outside joists. If the ceiling surface below is lath and plaster, take care not to jar it loose when nailing into the joists. Next nail the beam and the side of each joist together with a metal joist hanger. If two joists overlap beneath the beam, be sure to support both joists with a separate hanger. Once this process is complete, the joists are suspended from the beam and you can remove the wall. Follow the steps outlined earlier for removing a nonbearing wall.
To install a beam within the room, prepare the beam before you build the temporary supports. If the it with finishing material such as wallboard, you can build up a beam with three widths of 2-by lumber.
The exact length of the beam is difficult to determine until the existing wall is ripped out. H the new beam will run from wall to wall, the length is generally the width of the room, plus the thickness of both finish wall surfaces, plus the width of both side wall studs. Order a beam slightly longer than this. Then once the wall is down, you can take precise measurements and trim the beam to the correct length.
There are several techniques for building temporary supports. Some contractors use adjustable Lally columns, which are like screw jacks except that they in- dude a long length of heavy pipe, or prop the joists with A-shaped supports. The technique outlined here works well using 2-by-4 lumber. The process is similar to building a new partition wall, except that these walls are only temporary.
Because the supports will limit access, place the beam on the floor next to the wall first. If the space is tight getting the beam between the two outer walls, elevate one end of the beam and temporarily secure it. Be sure to protect any finish surfaces from gouging and scarring.
Cut two lengths of 2 by 4 the length of the wall to serve as top and bottom plates. Wider lumber can be used it you have it on hand. Next cut 2-by-4 studs the exact height of the ceiling, less 3 inches (the combined depths of the two plates). If the joists are 16 inches on center, cut enough studs for every other joist. If the joist spacing is wider, cut one stud for each joist.
If the ceiling surface is down, nail the top plate to the joists parallel to the bearing wall and 24 to 30 inches beam is to be visible, use solid lumber. If you plan to box away. If the ceiling surface is to be saved, cushion the top plate with a blanket or towels and have a helper hold it in place. Then wedge several studs between the top and sole plate. Position the studs beneath every other joist, beginning with the outside joists. If the studs aren’t snug, jam pieces of shim stock underneath to wedge them tight. Toenail the studs to the sole plate, but use double- headed nails or leave the heads exposed for easier removal. Check the position of the studs with a level to be certain they are reasonably vertical.
After this first support is in place, build an identical twin on the opposite side of the wall. One support alone won’t do the job. The joists must be shored up on both sides before the wall can be removed. These temporary supports don’t have to carry the entire weight of the house. Their purpose is to keep the existing structure from changing shape even slightly. If the ceiling joists are allowed to sag momentarily, you’ll have cracked plaster or wallboard to repair.
Once both supports are installed you can remove the wall, following the procedures outlined earlier for nonbearing walls. If the studs seem to be under a lot of pressure when you cut them, or if the ceiling begins to sag, tighten the temporary supports with additional shim stock or add more studs under the unsupported joists. Sometimes you can gauge the pressure before cutting by tapping the studs with a hammer. A solid, ringing sound indicates pressure.
Alter the studs are out, remove any extra studs in the sidewall that were part of the corner assembly. Cut the wall surfaces back to the nearest stud on either side of the opening. This provides access inside the walls to nail in the beam and posts. (Although you can toenail the post from the front only in order to minimize patching, this method isn’t preferred.)
If the new beam is to be covered, the two top plates can be left in place. Cut off any protruding nails flush with a hacksaw blade. However, the depth of the plates will lower the final height of the beam. If headroom is a problem, remove one or both top plates as explained earlier. Also pull up the sole plate.
Now you can measure and cut the beam to the correct length. You will also need to notch both ends of the beam to fit snugly under the top plates of the side- walls. If there are two plates of 2-by-4 stock, cut notches 3 inches deep and 3 1/2 inches long at the ends of the beam. Older homes may have only one top plate. Notch accordingly.
Next measure the height from the sole plate to the lower top plate and subtract the depth of the beam. Then cut the posts that will support the beam. The posts can be solid 4 by 4s or built up from two or three 2 by 4s so they are wide enough to support the beam with 3 plywood spacers between them. With a helper or two, lift the beam in place and wedge the posts beneath it. If some of the ceiling joists are lower than others and interfere, raise them by shimming up the appropriate studs of the temporary bracing. Check the posts with a level to see if they are plumb. If the walls aren't exactly plumb, then line up the posts with them. Toenail the posts to the beam and the sole plate. At this point you may need to provide support under the floor for this new post. Once the beam is securely nailed in place and the post is supported, you can remove the temporary supports and patch the openings in the wall and floor. Be sure a metal bracket connects the beam and post.
|Top of Page||HOME||Prev: Utility Systems||Next: Making Interior Changes: Cutting Into an Existing Wall|
Monday, June 7, 2010 15:31 PST