This is one of the most important questions in wood siding — and the honest answer is that several conditions tip the scale from repair toward replacement.

Improper flashing at windows and doors is one of the biggest flags. If water is getting behind the siding at those transitions, you're dealing with a systemic installation problem — not just a surface issue. Flashing failures allow moisture to work behind the siding and into the wall assembly over time, and by the time you see the damage on the exterior, there is usually significant damage hidden behind it. Repairing individual boards while the flashing issue remains will result in the same problem recurring.

Water infiltration from multiple locations is another sign. If you're finding moisture getting behind the siding in more than one spot — at window heads, at door jambs, at corner transitions — that is a pattern, not a one-off repair situation. It typically means the installation details were wrong from the start or have deteriorated to a point where piecemeal repair no longer makes economic sense.

Cost crossover is the third factor. There comes a point where the cost to properly repair all the damaged sections, re-flash the problematic transitions, and address the underlying causes approaches or exceeds the cost of a full replacement — which gives you new material, correct details, and a fresh start. IES Construction & Roofing will always give you an honest assessment of where your project falls on that spectrum.

Technically yes — wood siding can be installed directly over a properly prepared substrate. But at IES Construction & Roofing, we prefer a different approach, and the reason comes down to how wood behaves with moisture over time.

Wood siding — even naturally durable species like cypress and cedar — needs to be able to dry out from both sides. When siding is installed tight against a flat substrate with no air gap, any moisture that gets behind the siding has nowhere to go. It sits against the back face of the boards, accelerating the degradation of both the siding and the substrate behind it.

Our preferred approach is to install over a rainscreen — a drainage mat or furring strips that create a small air gap between the siding and the substrate — combined with a cedar breather product. The cedar breather is a mesh material that creates a continuous ventilation path along the back face of the siding, allowing moisture to drain down and air to circulate. This dramatically improves drying performance and extends the service life of the siding.

For a material like cypress or cedar where you're making a significant investment in natural wood, the added cost of a rainscreen assembly is one of the best investments you can make to protect that investment long-term.

Fastener selection for wood siding depends on the profile being installed — and getting it wrong causes visible problems that are difficult to fix.

For larger face lap siding like cypress board and batten, we face nail the siding. Face nailing means the fastener goes through the face of the board at the appropriate nailing point. With wide boards like our 9" cypress, proper face nailing placement is critical — nailing too close to the edge or in the wrong location restricts the wood's ability to expand and contract with moisture changes, which leads to splitting and checking.

For cedar shake and shingle siding, we prefer to use staples rather than nails in many applications. The reason is practical — staples hold the shake firmly without the shingle slipping on the nail shank the way it can with a round nail, especially on steep or vertical wall applications. The wider crown of a staple distributes the holding force across a larger area of the shingle face, reducing the risk of the fastener punching through or the shingle splitting at the fastener point.

The single most important rule for any wood siding fastener: it must be non-rusting. Stainless steel or hot-dipped galvanized fasteners only. Standard zinc-plated or bright nails will rust on contact with the tannins in cedar and cypress — producing ugly rust streaks down the face of the siding that are almost impossible to remove. It's a small detail that makes an enormous difference in the finished appearance of the installation.

Wood siding maintenance is a real commitment — and IES Construction & Roofing will always be honest about that before we recommend it. If you want zero maintenance, wood is not the right material. If you want the most beautiful, characterful exterior available and are willing to invest in keeping it that way, wood is extraordinary.

Paint or stain: Wood siding needs to be painted or stained to protect the surface from UV exposure and moisture. A quality paint or stain system on properly prepared cypress or cedar should last 5–8 years on most surfaces — longer on shaded walls, shorter on south and west-facing walls that take the most direct sun. Cedar and cypress take stain and paint exceptionally well, and the refinishing process is straightforward when done on a proper maintenance cycle.

Annual inspection: Walk the perimeter of the home once a year and look for cracked caulk at joints, checking or splitting at board ends, paint or stain failure, and any signs of moisture infiltration at windows, doors, and penetrations. Catching these early — a $20 tube of caulk and an hour of your time — prevents what would otherwise become a much more expensive repair.

Caulk joints: All joints where siding meets trim, windows, and doors should be inspected annually and recaulked wherever there is cracking or separation. This is the single most cost-effective maintenance task for wood siding — water infiltration at joints is where most wood siding failures begin.

Cleaning: A gentle rinse with a garden hose once or twice a year removes surface dirt and prevents mildew accumulation on shaded walls. Low-pressure washing is acceptable — never high pressure, which can force water behind the siding and damage the surface.

The honest answer depends heavily on the species, the installation quality, and how consistently the homeowner maintains it.

Cypress is the most durable option for St. Louis and Metro East Illinois — heartwood cypress with proper installation and a consistent maintenance cycle can genuinely last 50–100+ years. Century-old buildings across the American South — in climates that are directly comparable to St. Louis — still carry their original cypress siding. That track record is real.

Western Red Cedar typically lasts 20–40 years in St. Louis conditions with proper maintenance. The hot humid summers and hard freeze-thaw cycling we see in Missouri and Illinois are more demanding on cedar than the Pacific Northwest climate where it was historically specified. Cedar performs well when maintained — it struggles when maintenance cycles are skipped.

Installation quality is the largest variable. Wood siding that is improperly flashed, installed too close to grade, or fastened incorrectly can fail in 10 years or less regardless of species. Wood siding installed with proper details, correct fasteners, a rainscreen assembly, and appropriate end sealing on all cuts will dramatically outlast a poor installation of the same species.

This is a legitimate concern in the St. Louis and Metro East Illinois market — and the species choice matters enormously here.

Missouri and Illinois have significant termite pressure, and termites are the primary pest concern with wood siding in our market. Standard pine siding has essentially no natural resistance to termites and should not be used in our climate. Even cedar, which has better natural resistance than pine, is only moderately resistant — termites can and do attack cedar over time.

Heartwood cypress has the strongest natural insect resistance of any commonly available siding wood in our region. The cypressene oil content in cypress heartwood is naturally repellent to termites and most wood-boring insects. It is one of the primary reasons IES Construction & Roofing specifies cypress over cedar for lap siding in the St. Louis market.

Woodpeckers can also be a nuisance on wood siding — particularly cedar — as they drill looking for insects living inside the wood. This is less common on properly maintained, painted or stained siding, but worth knowing.

Regardless of species, keeping paint and stain in good condition, maintaining proper clearance from soil and vegetation, and ensuring no moisture is accumulating behind the siding all significantly reduce pest vulnerability.

Yes — and this is one of the genuine advantages wood has over fiber cement and vinyl. Wood siding can be painted any color, any sheen, and repainted a completely different color at any future maintenance cycle. You are never locked into a factory color the way you are with fiber cement ColorPlus or vinyl.

Cedar and cypress both take paint and stain exceptionally well. The key to long paint life on wood siding is proper surface prep and priming — all end cuts should be sealed before installation, and all field cuts made during installation should be primed on-site before the board goes up. Unprimed end grain is the most common entry point for moisture on painted wood siding, and it's completely preventable.

Paint vs. stain: Both are viable finishes for wood siding. Paint provides a more opaque, uniform finish and typically offers better UV protection — ideal for homeowners who want a specific color match. Semi-transparent and solid stains allow more of the wood grain to show through and are easier to maintain because they don't peel the way paint can. The choice depends on the look you want and your preference for the refinishing process down the road.