Avoid Framing Mistakes
Build your walls straight, sturdy and plumb with these great tips.
Avoid Framing Mistakes
We wanted to know which mistakes were the most common and how to avoid them. So who better to talk to than a building inspector? He shared his experiences, his insight and a few horror stories. We walked away with some great tips on how to build a rock-solid house, build it code compliant and build it right the first time.
Stagger the joints in the top plates
It’s best to have one continuous top and tie plate, but that’s not possible on longer walls. When multiple plates are necessary, keep top plate end joints a minimum of 24 in. away from tie plate end joints. And keep end joints at least 24 in. from the end of the wall as well. If the two end joints are not kept apart, they create a hinge point, which weakens the wall. But
24 in. is a bare minimum; most conscientious framers prefer at least twice that distance.
Nail to the framing
When you’re securing the bottom plates of walls to the floor, nail into the floor joists/trusses below. Nailing through the plywood keeps the wall from moving side to side, but expansion and contraction of the roof system could cause the wall to lift if it’s not also nailed to the floor joists/trusses. Plus, the nails will be out of the way when contractors need to cut holes in the plates for pipes, ducts and wires.
Don’t forget the connectors
Structural connectors are designed to hold framing members to the foundation and to one another. They help a building withstand heavy loads, strong winds and earthquakes. Building codes that require structural connectors have been changing as connector technology improves, so make sure to review your local codes and contact your local building department if you still have questions. The foundation straps shown here prevent high winds from blowing these small garage walls off the foundation.
Include finished flooring when laying out stairs
The highest riser (step) height cannot be more than 3/8 in. higher than the shortest riser height throughout the entire flight of stairs. Those measurements include finished floor heights. So mock up and plan for the final finished floor heights, top and bottom, before you begin doing the math and laying out the stair stringers.
Installing 3/4-in.-thick hardwood floors on a 1/4-in. subfloor will raise a floor height 1 in. Some carpet, vinyl and laminate flooring options are less than 3/8 in. thick. If you don’t account for those height differences, you could fail your inspection, and ripping out stairs is an expensive callback.
Use approved nails on treated lumber
Today, treated lumber intended for residential construction is protected with a copper-based preservative system called alkaline copper quaternary (ACQ). Whenever you’re working with ACQ lumber, be sure to use only ACQ-approved nails. ACQ treated wood is extremely corrosive to standard framing nails; they will actually dissolve when in direct contact with ACQ lumber. And if there are no nails holding wall studs to a treated bottom plate, foundation bolts/anchors are ineffective. It’s also important to use ACQ nails to secure the sheathing to a treated bottom plate.
Double up jack studs
Jack studs, or “trimmers,” are the framing members that support headers. The number of jack studs needed depends on the length (and sometimes the width) of the header. If the blueprints don’t specify, a good rule of thumb is to install two on each side if the opening is wider than 6 ft., the typical patio door size.
Check for crowns in the studs
This may seem like a “duh!” tip, but some carpenters don’t take the time to check the crown (bow) in every stud before assembling a wall. No one will notice if two studs with a 1/4-in. crown are aligned the same way. But if those same studs are installed on opposite sides of the wall, that 1/2-in. difference will be noticeable on both sides of the wall. Also, the studs may continue to warp as they dry, making the wave even more prominent. When you’re assembling walls on the ground, keep the crown side up. If the crowns face down, the studs behave like a rocking chair and make it harder to assemble the wall. Some builders use engineered lumber on walls where cabinets will be located because it’s super straight and stable.
Add squash blocks to carry loads
When a heavy load-bearing beam sits atop a wall, extra studs are needed to help carry that “point load” down to the bottom of the wall. But the story doesn’t end there; that load has to be carried all the way down to the foundation. Squash blocks are often required to bridge the gap between a beam-supporting wall and the wall beneath it. Either vertical blocks (photo above) or horizontal blocks (illustration at left) could work.
Don’t forget drywall backing
Most framing assemblies require extra backers to secure the drywall. Even if you’re conscious of installing drywall backers as you build, it’s easy to forget a section now and again. Don’t treat missing backers lightly; they can be a lot more difficult to install if there are wires, pipes or ducts in the way. Also, a grumpy drywall guy may have to rip off moisture barrier, pull out fiberglass insulation or chip out spray foam in order to hang the drywall. To make sure all the backing is there, one simple trick is to walk from room to room and scan every single wall and ceiling intersection with the thought of hanging drywall. And don’t forget the closets.
Don’t install joists under toilets
All blueprints should indicate the size and spacing of floor joists/trusses, but many don’t spell out their exact locations. Avoid installing floor joists/trusses directly in the path of large drainpipes and mechanical chases. Toilet locations usually cannot be moved, which means the plumber will have to cut into a joist/truss, which can mean hiring an engineer to design a repair, which takes time and costs money.
Reinforce doorway walls
A wall that supports a door takes a lot of abuse. Some solid-core doors weigh more than 100 lbs. Add an emotional, door-slamming teenager, and you have a door frame that needs to withstand a lot of force. It’s important to add extra support to doorway walls, both on the hinge and on the latch side. Do that by applying construction adhesive under the bottom plate on each side of the opening and by adding a couple of 3-in. toe screws.
Talk to the masons about anchor locations
Meet with the masons before they build the foundation. They should know that anchor bolts are required to secure wall plates every 6 ft. on center and within 12 in. from the ends and each side of joints. But sometimes anchors end up where they don’t belong, like in door openings or under jack studs. A short meeting to discuss locations of openings and splices could spare you from cutting out misplaced anchors and installing new ones.
Shelter your materials
A little moisture isn’t going to hurt most building materials, but if a project is delayed or you know you’re in for a long run of wet weather, cover your materials with a tarp. Long exposure to wet conditions can promote mold as well as cause engineered lumber to delaminate and framing lumber to warp and twist. Plus, no one wants to work with wet lumber! Keep the tarp a little loose at the bottom for air circulation.
Meet the expert
Don Sivigny saw a few framing mistakes and code violations in the 13 years he spent as a construction manager and general contractor, and the 21 years he worked as a building Inspector. Today Don is a construction code representative in the Construction Codes and Licensing Division for the State of Minnesota. He also represents the state when new building codes are being drafted.