Ask House Spouse · Exterior & Weatherproofing · Decks & Outdoor Structures
What does a deck repair cost in the Seattle area?
Short answer
Small repairs like replacing a few boards or securing a wobbly rail often fit into our minimum handyman visit, starting at $580 plus materials. More extensive repairs involving multiple joists or large sections of decking typically range from $1,500 to $5,000. The final price depends heavily on the extent of wood rot and whether structural components are compromised.
Common Deck Repairs and Their Costs
Deck repair costs are tiered based on complexity: * **Small Repairs ($580, $1,200):** Often covered by our handyman minimum service. This includes replacing 2-5 rotted deck boards, securing a wobbly handrail section, or replacing a single stair tread. The cost varies based on material availability and matching existing stain. * **Moderate Repairs ($1,200, $3,500):** This tier involves more substantial work, such as replacing a full section of decking, sistering a few rotted joists (adding a new joist alongside a compromised one), or rebuilding a small set of stairs. * **Major Structural Repairs ($3,500+):** This is when the deck's core integrity is a concern. Work may involve replacing multiple support posts, addressing a failed ledger board connection to the house, or a complete stair system rebuild. At this scope, it's wise to compare the repair cost to a full replacement.
The Biggest Cost Factor: Hidden Rot
The surface you see is only part of the story. A few soft deck boards can be the tip of an iceberg, hiding rotted joists or beams underneath. This is why a simple 'cost per square foot' is misleading for repairs. The true scope and cost are only revealed after we remove the surface boards to assess the condition of the substructure, which is a critical part of our diagnostic process.
Repairing vs. Replacing Your Deck
If your deck's substructure (the posts and joists) is sound and less than about 25% of the surface boards and railings need work, a repair is usually the most cost-effective path. If the foundation posts are failing, the ledger board is compromised, or a majority of the decking is rotted, the long-term value and safety of a full replacement often outweigh the cost of large-scale, piecemeal repairs.
Our Process for Durable Deck Repairs
We start with a detailed assessment to identify all compromised wood, both visible and hidden. Our repair process involves carefully removing all rotted material, replacing it with new pressure-treated lumber, and ensuring all new connections are secure and properly flashed to prevent future water intrusion. We handle everything from board replacement and railing fixes to stair rebuilds, leaving you with a safe and solid deck.
Why it happens
The primary cause is the relentless moisture of the Pacific Northwest. Inconsistent or neglected staining and sealing allows rain to penetrate wood fibers, causing rot to start at joints, fastener points, and unprotected end grains. Additionally, poor ventilation underneath a low-to-the-ground deck can trap moisture, accelerating decay in the joists and support posts where you can't see it.
How to diagnose it
- 1Probe for Soft Spots: Use a screwdriver or awl to firmly press into deck boards, railings, and support posts, especially near fasteners or where wood meets concrete. If the tool sinks in easily with a crunchy feel, it's a clear sign of rot.
- 2Check for Wobble: Firmly push and pull on railings and stair guards. Any significant movement or sagging indicates loose fasteners or rotted structural connections that require immediate attention for safety.
- 3Inspect the Ledger Board: Examine the board attaching the deck to your house. Look for a secure connection, proper flashing, and any signs of water staining on your home's siding, as this is a critical failure point.
- 4Examine Support Posts: Check the base of each support post where it meets its concrete footing. Look for signs of rot, soil contact, or insect damage. The posts are the foundation of your deck.
- 5Look for Widespread Cupping or Cracks: Visually scan the deck boards. While some cracking is normal, widespread cupping (where boards form a 'U' shape) and deep, splintering cracks suggest the wood is aged and has lost its integrity.
DIY vs. professional
DIY-friendly if…
DIY is appropriate for preventative maintenance like cleaning and sealing, or for replacing one or two easily accessible, non-structural deck boards.
Call a pro when…
Call a licensed contractor for any rot in support posts, joists, or the ledger board, wobbly railings, failing stairs, or if more than a quarter of your deck boards need replacement.
Cost expectations
$580–$5,000typical WA labor + materials
Covers a handyman visit for loose railings up to more extensive work like replacing several rotted joists and a section of deck boards. Materials are additional.
Every House Spouse job is quoted in writing before we start. 12-month workmanship warranty included.
What we see on Home Health Assessments
Around 74% of PNW roofs we assess show active moss establishment — accelerates shingle wear by an estimated 3–5 years if untreated.
Caught early on assessment: $220–$650 · Left until failure: $3,500–$22,000
A Home Health Assessment is perfect for this. We meticulously probe for early signs of wood rot in joists, posts, and the critical ledger board, identifying compromised flashing, loose railings, and drainage issues before they become major structural failures.
How the Home Health Assessment works