How To Install Furring Strips For Siding

Siding Installation

The walls of your habitation are an environmental separator. Their task is to keep the inside in and the outside out. Exterior cladding or siding is your first line of defense against weather elements, and its job is to permit interior control layers (ie. the building envelope) to do their jobs without existence assaulted by wind, precipitation and UV rays.

Walls in heating/cooling climates similar Canada demand to be designed to dry during all seasons, not just winter, which is how we most often build them at present.

Wet will always menstruum from areas of high concentration to depression, and the side of the wall those dissimilar weather condition are on will reverse between seasons due to insulation and/or air conditioning. In winter it is cold and dry exterior, in summer it is hot and humid outside, hence the demand to dry in both directions.

In social club for something to dry out, an exchange of energy needs to take place. When we oestrus a business firm, it dries outwards, when we absurd a house, it dries inwards (or at least information technology should - depending if you have a vapor bulwark). A well-ventilated air space between sheathing and cladding is an important office of the strategy needed to allow walls to shed moisture in all seasons and atmospheric condition.

Drainage planes (building newspaper, house wrap, etc.) allow any moisture that does accrue backside siding a take a chance to bleed away harmlessly. The air space betwixt siding and capsule should too allow humid air to escape. In order for both of these actions to have identify, when siding is installed correctly at that place needs to be a continuous space behind siding where water can bleed and air tin menstruum.

Common siding installation mistakes to avert:

Caulking the top cladding board to trim boards: This creates a dead end that traps humidity in walls behind siding.
Cutting boards short and relying on caulking to fill the gap: Caulking will eventually fail, letting water in but besides potentially keeping it in. Boards are best installed tight, a certain corporeality of shrinking will occur only whatever water that gets in volition be able to dry. Exist certain to seal all cut ends with pigment.
Installing horizontal furring to attach siding: If your siding requires horizontal furring (such as board and batten), install a outset layer of vertical furring to allow a drainage cavity, then a 2nd layer. Horizontal furring strips tin stop air catamenia and prevent h2o from draining out. Diagonally installed furring is an choice that can also work without needing a second layer.
Double furring at the corners: corners are often needlessly fortified with furring strips (or strapping), where they should ideally be left open and able to dry out. If water is going to leak into walls information technology will be at joints and junctions like corners.

Air spaces behind siding allows water to drain and moisture to escape. © Ecohome

How much of an air space is needed behind cladding?

The air space betwixt cladding and sheathing doesn't need to exist great but information technology needs to permit continuous drainage without creating pockets where water can be trapped within wall assemblies (referred to as perched water). Correctly installed siding should also let air to period through from top to lesser, taking advantage of natural convection to remove moisture.

1x4 and 1x3 furring are about commonly used equally they are easily bachelor and affordable, simply that doesn't hateful you lot can't observe even cheaper alternatives that could save some wood and mayhap some money for someone that likes a DIY project. If y'all have enough material to meet your needs, you could use erstwhile floor, even former plywood ripped into strips on a tabular array saw.

An air space of even 1/eighth of an inch volition do the job, so what y'all use equally furring is actually only a spacer and isn't as well important every bit long as your siding can grab information technology, or grab the sheathing behind with longer nails. The most important affair is that the material exist consequent in size to avoid walls looking warped.

Air space behind siding for drying and drainage

Air space behind correctly installed siding for drying and drainage © Ecohome

Can you proceed water and wet out of walls?

Some of the things nosotros practise that were originally intended to proceed walls dry out (polyethylene vapour barriers, for case) are now more normally keeping them wet. Nosotros accept grown to rely heavily on caulking - frequently referred to every bit 'liquid carpenter' - equally a a cure-all for every mistake, and to let for quicker installation by cut less precisely.

Caulking on poorly installed siding always looks dandy at offset, but it will break down over time (more quickly on south facing walls), and at some indicate may actually hold water in instead of keeping information technology out.

Setting out on a mission to stop all water and moisture from ever getting into your walls volition more likely ensure that they volition become wet and stay moisture. The walls that volition final the longest are the ones that have been designed to realistically manage moisture and dry, not those designed to achieve the unachievable. With a few cloth exceptions of class, for the most part information technology is okay for walls to get a litte wet as long equally they can as well dry out.

An analogy on this topic credited to Professor John Straube of the University of Waterloo may help yous have this defeat graciously: with a price tag of several billion dollars, a Trident ballistic nuclear missile submarine is one of the most sophisticated and expensive machines ever made. With unlimited funds and access to the most advanced technologies, in the cease they notwithstanding assume water will leak in and they install a pump. Decision: yous tin't build something that doesn't leak, so focus on making sure it tin can dry when it does.