Shade Sail Posts & Mounting
Handis shade sail post and mounting puts the structural rigging for a residential shade sail (triangular or rectangular sun-shade fabric) on a deck, patio, or backyard — cedar or aluminum posts set in concrete footings, marine-grade 316-stainless eye-bolts and turnbuckles at every corner anchor, 3-anchor and 4-anchor configurations — from $800 for a 1-to-3 anchor mount on existing eaves, decks, or posts to $2,500 for a four-post 6x6 cedar post system in concrete. Shade sails are the budget shade fix — a $200 to $600 fabric sail tensioned between three or four anchor points casts a triangular or rectangular shaded area on the deck or patio below, with the sail going up the first weekend of June and coming down the first weekend of October as the PNW summer cycle dictates. The structural rigging is the part that matters — the sail fabric is bring-your-own (Handis installs the rigging, the homeowner buys and changes the sail), and the right post-and-eye-bolt configuration is what keeps the sail tensioned correctly through 4 to 5 months of summer wind and prevents the corner anchor pulling out of the eave or the post in a gust.
Service
What Does a Shade Sail Post & Mounting Install Include?
A shade sail post and mounting install is the structural-rigging carpentry service that puts the post-and-eye-bolt infrastructure for a residential shade sail on a deck, patio, or backyard — covering site review and corner-anchor layout for the planned sail size and shape (triangular, rectangular, or square), structural review of any existing structure (eave, deck, existing post) that will receive an anchor, footing dig with a power auger to 24 to 30 inches below grade with Simpson ABA or ABU post-base anchors on new-post installs, cedar or aluminum post-set, marine-grade 316-stainless eye-bolts and forged turnbuckles at every corner anchor, and seasonal-tension instructions for the homeowner. Handis covers shade-sail installs from $800 on the 1-to-3 anchor mount on existing structures up to $2,500 on the four-post 6x6 cedar system in concrete. Shade-sail fabric is bring-your-own (homeowner-supplied).
Bring-Your-Own Shade Sail Fabric
Shade sails come in a wide range of shapes (triangular, rectangular, square), sizes (8-foot through 20-foot sides), colors (sand, terracotta, charcoal, grey, blue, green), and fabrics (HDPE knitted shade cloth at 90-95% UV block, PU-coated waterproof options at higher cost). Sail manufacturers (Coolaroo, ShadeMaster, Sun Squad, Sail Shade Center, Amazon house-brand options) sell direct to homeowners at $80 to $600 depending on size and fabric. We do not sell or stock sails because the homeowner is the right party to pick the shape, size, color, and fabric for the use case. Handis installs the structural rigging that holds the sail.
Marine-Grade 316 Stainless Hardware Throughout
Every corner anchor uses marine-grade 316-stainless eye-bolts (the highest-corrosion-resistance stainless grade for outdoor coastal exposure) and forged 316-stainless turnbuckles for the seasonal tension adjustment. Standard galvanized or zinc-plated hardware corrodes against the wet PNW climate and the salt-air on coastal-influenced sites within 18 to 24 months and seizes up — the turnbuckle that should adjust seasonally becomes a frozen lump after the second winter. 316 stainless costs more per piece, lasts the life of the post, and stays adjustable.
3-Anchor Triangular or 4-Anchor Rectangular Configurations
Three-anchor (triangular sail) is the most-common shade-sail configuration — three corner anchors arranged in a triangle around the area to be shaded, sail tensioned between the three points, casting a triangular shadow. Four-anchor (rectangular or square sail) gives a larger shaded area and a more controlled shadow shape, requires the additional fourth anchor (one more post or one more eave mount), and is the right choice for shading a dining table or a longer seating cluster. We recommend the configuration on the site visit based on the area to be shaded and the available anchor points (existing eaves, existing posts, where new posts can go).
Cedar or Aluminum Posts in Concrete Footings on New-Post Installs
New-post installs follow the same footing standard as our pergola builds — power-auger every footing to 24 to 30 inches below grade, pour concrete around a Simpson ABA or ABU post-base anchor set plumb in the wet pour, 48-hour cure before the post is raised. Cedar posts are 4x4 Western Red Cedar on standard installs, stepped up to 6x6 cedar on larger sails or higher-wind sites. Aluminum posts (powder-coated steel-shrouded aluminum or solid aluminum) are an option for the modern look or when the homeowner prefers a non-wood post. Post height typically 9 to 12 feet so the sail can tension high enough to provide standing-headroom shade.
Retrofit Mounts on Existing Structures (1-3 Anchors)
Retrofit installs mount eye-bolts on existing structures — the eave of the house or garage (anchored into the rafter tail or the structural fascia), an existing pergola or covered cover post, a deck rail (through-bolted into the rail structure), or an existing 4x4 fence or yard post. Retrofit installs avoid the footing dig and the 48-hour cure, run faster (usually a 1-day install), and cost less than the new-post equivalent. We review every existing-structure anchor on the site visit to confirm it can take the sail load (typically 100 to 300 pounds of tension per anchor at full sail load on a windy day).
How a Shade Sail Post Install Works
Six sequential steps from site review through seasonal-tension handoff — the actual sequence we follow on every shade-sail post and mounting install.
Site Review and Anchor-Layout Planning
Tech walks the deck or patio, confirms the area to be shaded, identifies the available anchor points (existing eaves, existing posts, where new posts can go), recommends the sail configuration (3-anchor triangular for simpler installs, 4-anchor rectangular for larger shaded area), and confirms the anchor-to-anchor distances against the homeowner's planned sail size. Structural review of any existing structure that will receive an anchor — eave rafter, deck rail, existing post.
New-Post Installs — Power-Auger Footings, 48-Hour Cure
On new-post installs, power-auger every footing to 24 to 30 inches below grade with the diameter sized to the post and the wind-load on the planned sail. Pour ready-mix concrete around Simpson ABA or ABU post-base anchors set plumb in the wet pour. 48-hour concrete cure before the post is raised. Retrofit installs (mounting on existing structures) skip this step.
Raise the Cedar or Aluminum Posts
Cedar 4x4 or 6x6 posts (or aluminum posts) lifted onto the cured ABU anchors and through-bolted with the post-base hardware. Each post plumbed against a 4-foot level on two faces. Post height cut to spec (typically 9 to 12 feet so the sail tensions high enough for standing-headroom shade). Posts braced against any movement until the eye-bolts are installed.
Install Marine-Grade 316-Stainless Eye-Bolts
Marine-grade 316-stainless eye-bolts installed at the top of each post — drilled and through-bolted (cedar posts) or welded-to-bracket-and-bolted (aluminum posts), with the eye facing the sail direction. The eye-bolt takes the full sail tension at the corner — typically 100 to 300 pounds at full sail load on a windy day, more on larger sails. 316 grade chosen for the corrosion resistance through PNW winters.
Install Forged 316-Stainless Turnbuckles
Forged 316-stainless turnbuckles rigged between the eye-bolts and the sail-corner D-rings — the turnbuckle adjusts the sail tension for seasonal tightening and slackening (sails are slacked over winter when removed and re-tensioned each spring). Turnbuckle sizing matches the eye-bolt and the sail-corner hardware. Carabiners and quick-release snap shackles available as an upgrade for easier seasonal removal.
Demonstrate Seasonal Tension and Hand Off
With the sail rigged (using the homeowner's purchased sail), demonstrate the turnbuckle tension adjustment — how to tension the sail correctly (taut but not over-tensioned, with a slight visible curve to the sail face) and how to slacken or remove the sail for winter storage. Written care sheet covering tension target, seasonal removal recommendation, and storage instructions. The homeowner manages the sail for the life of the install.
Shade Sail Posts & Mounting Pricing
Final pricing depends on the number of anchors (1 to 4 corner anchors), whether the install is on new posts in concrete footings or retrofit on existing structures, post material (cedar standard, aluminum upgrade), post size (4x4 standard, 6x6 heavy-duty), and any add-ons (carabiners or snap shackles for easier seasonal removal). Shade-sail fabric is homeowner-supplied. Request a free estimate for an accurate quote.
Tell us the area to be shaded and where the corner anchors can land (existing eaves and posts, plus any spots a new post can go) — we will quote the post-and-mounting build with the right cedar-or-aluminum spec for the wind load.
Why Handis for Shade Sail Post & Mounting Installs
Shade sails are the simplest shade infrastructure in the pergola-and-shade family — and the lowest cost on this hub, which is exactly why some homeowners pick them. A 4-month summer in the PNW does not justify a $12,000 louvered system for every yard; a $800 to $2,500 shade-sail post system plus a $200 to $400 fabric sail covers the same June-through-September shading need at a fraction of the cost. The trade-off is the seasonal labor (the sail goes up the first weekend of June and comes down the first weekend of October before the wet wind season — leaving the sail up year-round is what shreds it in November) and the lower visual permanence (a shade sail is fabric, not architecture). The right scope split is the structural rigging done permanently and correctly (Handis), and the sail itself owned and managed seasonally by the homeowner (you pick the size, color, fabric; you put it up and take it down). That split is honest about who is the right party for each piece of the work.
Marine-grade 316 stainless on every anchor — non-negotiable
Every eye-bolt and every turnbuckle on every install is marine-grade 316 stainless steel — the highest-corrosion-resistance grade of stainless for outdoor PNW exposure. Standard galvanized or zinc-plated hardware corrodes against the wet climate within 18 to 24 months and the turnbuckle seizes up — the seasonal tension adjustment becomes impossible after the second winter. 316 stainless costs more per piece, lasts the life of the post, and stays adjustable year after year. We do not substitute the cheaper hardware because the failure mode is a sail-corner anchor that cannot be re-tensioned in spring.
Structural review of every existing-structure anchor
Retrofit installs mount eye-bolts on existing structures — eaves, decks, existing posts. We review every existing-structure anchor on the site visit to confirm it can take the sail load — typically 100 to 300 pounds of tension per anchor at full sail load on a windy day, more on larger sails. An eave anchor needs a structural rafter or fascia bearing surface; a deck-rail anchor needs the rail through-bolted into the deck structure (not just nailed into the post tops); an existing-post anchor needs the post properly footed. Where the existing structure cannot take the load, we install structural blocking ($250 add-on) or recommend a new post.
Cedar 4x4 standard, 6x6 on larger sails or higher-wind sites
New-post installs default to 4x4 Western Red Cedar posts on standard residential shade-sail installs. Larger sails (16+ feet on a side) and higher-wind sites (exposed bluff, foothill, near-water) step up to 6x6 cedar posts for the additional structural capacity — a 6x6 post bends substantially less under wind load than a 4x4 and stays plumb through the design wind event without permanent deflection. We recommend the post size on the site visit based on the sail dimensions and the site wind exposure.
Concrete-set footings to 24-30 inches — same as pergola spec
New-post shade-sail installs get the same footing treatment as our pergola builds — power-auger every footing to 24 to 30 inches below grade, pour concrete around a Simpson ABA or ABU post-base anchor set plumb in the wet pour, 48-hour concrete cure before the post is raised. The footing is what keeps the post plumb against the sail tension and the wind load — a shade-sail post on a buried 4x4 (the DIY shortcut) tilts within 12 to 18 months under the sustained corner tension and the wind cycle.
Seasonal-tension instructions handed off to the homeowner
Shade sails are seasonal infrastructure — the sail goes up in spring (typically the first weekend of June in Seattle), comes down in fall (typically the first weekend of October before the wet wind season), and gets re-tensioned mid-summer if the fabric stretches under sustained sun. We hand the homeowner a written care sheet covering the tension target (taut but not over-tensioned, with a slight visible curve to the sail face — over-tensioning shortens the sail life and stresses the corner anchors), the seasonal removal recommendation (sails left up through PNW winter wind get shredded), and the storage instructions. Optional seasonal-removal-and-re-hang service available at $200 per visit.
One-year project warranty on post-set and hardware
One-year project warranty on our install scope — post-set (on new-post installs), eye-bolt and turnbuckle install, structural review of existing-structure anchors, seasonal-tension demonstration and care-sheet handoff. The shade-sail fabric itself is homeowner-owned and managed; warranty on the sail comes from the sail manufacturer. The structural rigging (posts, eye-bolts, turnbuckles) lasts the life of the cedar (18 to 25 years on 4x4, 25+ on 6x6 heartwood) given the concrete footings and the 316-stainless hardware.
Estimate
Tell us the area you want shaded (the deck dining area, the patio seating cluster, the kids' play area), the anchor options you have (existing eaves on the house, existing pergola or fence posts, places in the lawn or patio where new posts can go), the planned sail size and shape if you have one in mind (triangular 12-foot sides, rectangular 10 by 14, square 12 by 12, etc.), and the seasonal-use plan (summer-only or year-round). We confirm the anchor structural review and the post-size spec on the first visit.
Customer Reviews
Shade sail post and mounting reviews from real Handis customers.
Four-post 6x6 cedar shade-sail system over our paver patio in Issaquah — we get strong afternoon sun and wanted real shade without committing to a full pergola. Handis set the four posts in concrete footings, ran the marine-grade 316-stainless eye-bolts at the top of each post, and rigged the rectangular sail we had already bought from Coolaroo. Sail goes up the first weekend of June, comes down first weekend of October, and the posts read clean as a furniture piece in the off-season.
Three-anchor retrofit mount on our Magnolia deck — two existing eaves on the house and one new 4x4 cedar post in the corner of the deck for the third anchor. Handis structural-reviewed the eaves (one needed a small blocking reinforcement, $250 add-on), installed the 316-stainless eye-bolts and turnbuckles, and we hung our triangular Coolaroo sail. The shade lands exactly on the dining table where we needed it. $1,100 done.
Mounting-hardware-only retrofit on our Bellevue deck — three anchors on the existing covered patio cover posts and the eave of the garage. No new posts needed because the existing structures could take the load. Handis confirmed the structural review on each anchor, installed the eye-bolts and turnbuckles in a half-day visit, and walked us through the seasonal tension. $800 done, fast turnaround.
Two new 4x4 cedar posts plus two retrofit anchors on existing fence posts in our Ballard backyard. Handis set the two new posts in concrete on the property line side, used the existing 4x4 fence posts on the house side for the other two anchors, and rigged the rectangular sail we bought on Amazon. Marine 316 stainless on every anchor — the turnbuckles still adjust smoothly three years in. Sail goes up and down every season without trouble.
Aluminum-post upgrade on our Mercer Island patio — wanted the modern look so we paid the per-post upgrade ($300 per post on four posts) for powder-coated aluminum posts instead of cedar. Custom dark grey powder-coat color upgrade to match the house trim. Marine-grade 316-stainless eye-bolts and turnbuckles same as the cedar configuration. Posts read clean and contemporary year-round.
Frequently Asked Questions
Common questions about Handis shade sail post and mounting installs.