In an abridged extract from Decks, David Toht looks at laying decking
Decking is the most dramatic stage of building a deck. After the heavy lifting of installing footings, posts, beams, and joists, you’ll at last have something you can stand on, something that really looks like a deck. And, if your deck calls for fascia and skirting, you are going to end up with a truly finished project. When ordering decking, allow for about 10% waste and error – 15% if you are installing the planks at a 45-degree angle. Have the material delivered well before you need it so you have recourse in case of a mistake in colour or type. Store your decking level and supported every couple of feet if you are using synthetic decking. Cover the decking with a tarp.
Plan your layout before installation. Give thought to the most visible areas of the deck. For example, decking near the main access should be free of unsightly gaps or butt joints. With wood, the main access area is the place to be the most selective about grain and any imperfections that wouldn’t be noticed elsewhere. Avoid having to end with a thin strip of decking somewhere.
Installing the planks is repetitious and a little mind numbing. Stand up every few courses and take in the big picture. Measure often to confirm you are parallel with the outer edge of the deck, and stretch a line to be sure bends in the planks are not being compounded as you work.
Culling your wood
Number 2 grade 5/4 x 6 cedar decking will inevitably have flaws you’ll want to hide, cut off, or in rare cases, reject.
Installing wood decking
Cedar and pressure-treated wood remain popular choices for decking. They are affordable, easy to work with, and offer the warm good looks of something that came from a real tree. Wood is easy to handle and shape and takes stain and other finishes well. While a circular saw is more than up to the job, a sliding power miter saw on a stand with long supports will yield the most precise cuts. If you opt for using a circular saw, arrange planks and scraps on sawhorses to fully support your work.
Unless you are lucky enough to plan your deck around full lengths of decking – the best approach for a sleek-looking deck – leave at least 32 in. between adjacent butt joints and stagger any joints by at least two planks. Don’t get your hopes set on doing any miter joints to try to achieve a snazzy look at the corners. Wood moves too much over its life for it to hold a tight miter.
Mind the gap
Time was when decks were gapped 1⁄8 in., mainly because spiky high heels would get caught in anything larger. The downside of such a small gap is that it readily clogs with debris. A 3⁄8-in. gap drains well, carrying away most leaves and dirt. It’s up to you to anticipate the dress code for your deck entertaining and gap accordingly. Using a 1⁄4-in. gap is a nice compromise.
For pressure-treated decking, the boards can be secured with no gap. Given their high moisture content—you’ll notice as you heft one—the gap will open as the wood dries to yield a 1⁄8-in. gap. Use a spacer if you want a larger gap. Here’s how to make your own spacers out of 1⁄4-in. hardboard and 1x4s. Select a scrap of hardboard equal in thickness to the gap between planks you want. Cut a dozen orso pieces about 2 in. by 3 1⁄2 in. Drill two 1⁄8-in. holes for nailing. Cut an equal number of approximately 4-in.-long pieces of 1×4. To eliminate any wiggle, apply woodworker’s glue to the 1×4 piece before nailing. Complete the spacer by using 4d nails to nail the hardboard onto the 1×4 pieces.
Using a guide
A straight 1×4 attached to the deck mcan be a helpful sawing guide, but it is not fail-safe. Lose your concentration for a moment and the blade can wander or bind. If possible, try cutting with and without a guide to see which you are most comfortable with.
Fastening ipe and other hardwoods
The installation of ipe and other exotics differs from softwood decking only in that exotics are notoriously hard to cut and drill. Carbide tips help, as does buying sawblades with thin kerfs. Be prepared for slow work and burning through a lot of blades. Given the high cost of these woods, you probably don’t want your deck marred by fastener heads. Here’s a method for making them disappear.
Tip
Ipe plugs are available for purchase online by the bag. Available diameters include 1⁄4 in., 3⁄8 in., and 1⁄2 in.
Stagger your joints
For a seamless look, leave minimum of 32 in. between nearby butt joints. Never stack joints. Instead, stagger them by at least two planks.
Installing synthetic decking
As manufactured products, PVC and composite decking have more precise installation requirements than wood. For example, the flex in the materials lets it conform to any irregularities in the framing – good reason to sweat the details in getting your frame perfectly smooth. Recommended fasteners must be used according to the manufacturer’s specified method. Where the decking abuts the house, leave a gap to allow for expansion and contraction as temperature changes.
The following steps show the installation of PVC decking, a process similar to that of composite decking. The only significant difference is the handling of miter joints. PVC decking joints can be glued with PVC adhesive for very strong joints. Composite decking typically requires a biscuit joint and exterior glue.
Stair-Step the Joints
Tip
Store synthetic decking on a clean, level area. Support the stack every few feet. Avoid introducing bends you may have to wrestle later by stacking the planks neatly and evenly. Dew and rain won’t harm synthetics, but for ease of handling, cover them with a tarp at night.
Making joints
With wood decks, it is possible to drill pilot holes and toenail fasteners into the joists. However, with time, cracks may show at the edge. A better approach for butt joints, and one required by some synthetic decking manufacturers, is to attach 2×4 cleats and install fasteners perpendicular to the surface.
Tips
- If for some reason you need to detach a piece of decking you’ve already fastened and plugged, don’t give up hope. Remove the plug by drilling a fastener into it and prying it upward and out.
- A double course of decking in a contrasting colour gives your deck an elegant picture-frame effect.
Graphic Insets
Because synthetics come in a wide range of colours, won’t split even when cut into small pieces, and can be shaped and smoothed easily, they are ideal for graphic insets. This orca design was made with PVC decking on a fiberglass grid.
For best results with synthetic decking
- Mix lots of synthetic decking to avoid any color shifts in the surface.
- Flop every other board to vary the look of the grain.
- Drill pilot holes for fasteners when close to the edge or at plank ends.
- To prevent immediate or eventual splitting at the ends of boards, don’t overtighten fasteners.