Strapping a ceiling in preparation for drywall is not especially difficult or complicated, but haphazard measuring can result in doing the job twice. Strapping a ceiling is a traditional method of flattening a ceiling (or another surface) to improve the performance and look of drywall.
Technically, installing any material on a large, open surface like a ceiling will require strapping, but since most structures have drywall, today that will be the focus. Installing ceiling strapping is often well within the skills of an amateur do-it-yourselfer.
Strapping is essentially the process of installing narrow strips of lumber, usually 1” x 3” or 1” x 4”, perpendicular to the truss chords or ceiling joists of a structure. This serves to strengthen the roof system while providing a solid attachment point for the drywall. As mentioned, strapping is also used to flatten an otherwise wavy surface. Especially when the ceiling is large, this technique greatly improves the look and longevity of the drywall.
How Long Does it Take to Install Strapping On a Ceiling
The time required to install strapping on a ceiling will be affected by the height of the ceiling and obviously, the size. As a rule, professionals can strap a ceiling in just a few hours using time-saving tools like laser levels and pneumatic nail guns. However, ceiling strapping can be done with hand tools only when required. Installing ceiling strapping will use several tools, but the project can be completed in any number of ways. Here is a sample of a few of the tools commonly used in ceiling strapping:
- Measuring Tape
- Chalk Box
- Corded or Cordless Drill
- Step Ladder(s)/Walkboard
- Framing Square
Recruiting additional help is always a good idea as well. Ceiling strapping usually involves long lumber, so having help to hold the strapping in place during installation is very handy. Strapping is not usually heavy nor awkward to handle, but it is important to keep it square to the walls. Keeping the strapping as close to 90 degrees from the walls as possible will reduce or eliminate most problems that occur.
The height and pitch of the ceiling will have a dramatic effect on the ease of installation. For example, in a typical ranch-style home the ceilings will be parallel to the floor, and usually no more than 10’ high. Many times the ceiling is only 8’ high, which is even easier. This makes the installation of strapping fairly quick and painless, however, other situations can be much more complex.
In a home with vaulted or cathedral ceilings, the project becomes considerably more difficult. In these situations, professional installers will often construct a movable platform using ladders and a walkboard. If the project is large, often scaffolding will be more effective.
Size Of the Drywall
In most circumstances, the larger the drywall panels, the better the final results will look. This is because larger panels reduce the butt joints created when two panels meet end to end. The short sides of drywall panels do not incorporate the indentions found on the long sides. This indention, when placed adjacent to another panel, creates a space for the drywall tape and compound. Therefore, butt joints are particularly vulnerable to a less than a flat surface. Installing strapping allows the installer to correct most issues that would affect the overall appearance of the final product.
Condition Of the Surface
Trusses and ceiling joists will often twist and sag over time, which is what usually causes unattractive, wavy-looking ceilings. This is especially prominent in older, hand-built (also known as “stick framing”) structures with ceiling joists because the bearing walls are often too far apart by today’s building standards. Trusses eliminate this problem and take advantage of bridge-like engineering techniques, often resulting in more open and airy rooms.
This is in contrast to stick framing, which employs other framing components like collar ties and ridge boards to prevent the structure from separating over time. Before the introduction of trusses, this was the standard construction method used in building many homes. However, regardless of the techniques used, the same concerns will apply when installing drywall.
Uneven trusses and ceiling joists are the primary culprits of rough-looking drywall. This is often because the tolerances required in rough framing are larger than those for fine carpentry. For example, it is not uncommon for the bottom chord of a truss or joist (the part the drywall attaches to) to be out of plane by ½” with another truss only 24” away. Therefore, it is usually recommended to install ceiling strapping before attempting a ceiling drywall installation.
Tools and Assistance Available
Strapping a ceiling for drywall can become a tedious project because the installer is always working overhead. This can lead to fatigue and the need for an extra pair of hands. Although it is possible to install strapping solo, doing so often requires the use of shorter lumber. Generally speaking, longer strapping tends to be straighter and stronger, so the best practice should involve some assistance.
If no assistance is available, T-stilts can be built to assist the solo installer. A T-stilt is usually just a 2” x 4” with another shorter 2” x 4” attached to one end. This 2” x 4” is then cut to length, so that when it is standing perfectly plumb it provides support for the strapping. When building a T-stilt, the pros will measure several places around the room from floor to ceiling and take the average measurement. For example, if the ceiling is 96” from the floor, and the installer is using 96” lumber he or she will cut off about 1 ½”. This will make room for the shortboard, which is 1 ½” thick. When these are connected, the result is a T-stilt exactly 96” tall.
Pro Tip. When building a T-stilt, the pros will usually add an additional ½” to the length. This allows them to lean the T-stilt in places too low and stand it straight in higher areas.
As mentioned earlier, the skills required for strapping a ceiling are not considered advanced. Do-it-yourselfers can typically install ceiling strapping, but caution should be employed when using any tools, especially on ladders. Obviously, the higher the ceiling, the more difficult the installation will be in most cases. Therefore, if a ceiling is particularly high and/or vaulted often hiring a professional is advised.
Although the actual installation process is not considered difficult, getting to the job may be. Professionals will have any number of tools such as scaffolding, ladders and walk boards, and even hydraulic lifts.
Most professionals will also use pneumatic tools such as nail guns to reduce fatigue and ensure a solid connection. In most cases, investing in these tools for one-time use is not practical. So depending on the situation hiring professionals may be the best overall solution, because these tools make installing the strapping much faster and more importantly, safer.
How Much Does Installing Strapping On a Ceiling Cost
The final cost of course will depend on the size of the project, the materials, and the labor. Although the cost will vary from region to region, most professionals charge between $2.00 – $4.00 per square foot, installed. The cost can be reduced by buying strapping materials in bulk and doing some, or all of the labor yourself.
Other synthetic materials are also used in strapping, but the most cost-effective method is to use #3 1” x 3” or 1” x 4” pine lumber. This lumber will usually have cosmetic defects, including a rough surface and sometimes bark. This type of lumber is great for strapping, as it’s really just a filler and will not be seen.
How to Get Started Installing Strapping On a Ceiling
Step 1. Inspecting the Surface
The primary function of strapping is to flatten a ceiling and provide a larger nailing surface for the drywall. Depending on the drywall finishing, a #3 finish is typically the goal. In most areas, this is the commercial and residential industry standard. Installing strapping can be accomplished in a number of ways, but for a #3 finish, the ceiling should have no visible waves or undulations. For comparison, a #5 finish (the highest quality possible) has no visible blemishes at all.
Strapping for a #3 finish can be measured by using the straightest, longest board available. With assistance, the installer will use this board as a guide and place it edge side up against a truss or joist.
Then pivoting in a semi-circle, a helper spins the board, noting if a truss is too high, too low, or just right. The helper will then mark each location and what needs to be corrected. These marks are made boldly along the area to be strapped so they are difficult to miss. Then the strapping is installed and using the marks, moving each strap slightly up or down as needed, by driving in shims between the strap and the truss. This allows for great precision and results in a very flat, stable ceiling.
Step 2. Laying Out the Area
The easiest way to calculate the materials needed for a strapping project is to measure the wall to wall length, parallel with the trusses. This measurement is then divided by 16, or whatever the required spacing is between fasteners when installing the drywall.
For example, let’s say there is a 20’ x 16’ room and the trusses run in the 16’ direction. If we convert to inches, we get 320” from wall to wall. If we divide this by the required spacing of the fasteners, which in this case is 16”, we see that we will need 20 straps. It doesn’t end there, however, as we need to add one more to allow for a close connection to the opposite wall.
Step 3. Installing the Blocking
Although not technically part of the strapping process, blocking will usually also be required. This blocking serves as a connection point for the drywall when obstacles get in the way. Also called “dead wood”, this blocking is usually trimmed and cut to fit anywhere a connection would otherwise be impossible.
This could be around a plumbing pipe, ductwork, or any other void. Blocking is usually built from scrap materials because it often has to take unusual shapes to fit the location. This method saves materials and greatly reduces scraps that might otherwise spend eternity in a landfill.
The blocking can be installed using nails, screws, adhesives, or any other solid connection method. In most cases, professionals will use a pneumatic finish nailer. This is because these nailers require the least physical effort as well as reducing the chances of splitting small bocking with the nail. Larger blocking, such as may be required along an entire wall, is typically built from standard lumber and installed using #12 to #16 framing nails.
Step 4. Mounting the Strapping to the Ceiling
After all of the marks have been made to indicate the location of the strapping, installing the straps is relatively simple. Using a helper or T-stilts, the straps are usually driven in using #6 to #8 ring shank or twist shank nails, although drywall screws are also appropriate.
Making sure to align the straps with the marks, the installer usually will install just one fastener (either a nail or screw) per truss. This is because the truss (or joist) is usually just 1 ½” wide, and attempting to install more than one fastener will often split the wood. This method also reduces the chances of hitting a nail head with a drywall screw when installing the drywall.
Once the strapping has been completed, the pros will often refer back to the long lumber used to determine the condition of the trusses. If any strapping is found to be too high, small shims can be added. If the marks were made accurately in the beginning, in most cases lowering high spots will raise the low ones, evening out the surface.
Can I Install Ceiling Strapping Myself?
As mentioned earlier, adding ceiling strapping is often a DIY project. There are no specialty tools required in many cases, so a homeowner will likely already have the tools required.
Installing strapping also provides practice using tools and measurements for the budding do-it-yourselfer, without much of the danger involved with similar projects. However, installing strapping does require some accurate calculations and comfortability with tools. For homeowners with the experience to use tools safely, adding strapping to a ceiling can be a worthwhile project.