Trouble collects in the last foot of a wood fence run. A board or post meets the siding there, rain running down the wall lands on the joint, and whatever sits against the house holds that water for as long as the two surfaces touch. Where a run reaches the house, it can end in one of two ways: fastened to the wall, with the last post or a vertical board screwed or bolted through the siding, or at a free-standing end post set in the ground just off the wall, with nothing tying the fence to the house. Both close the line. They do very different things to the siding, the wall behind it, the insects that travel along wood, and the next person who has to paint or re-side that wall.
Two Ways a Run Can End at the House
At one end, the fence uses the house as its last support. A board is fixed flat against the siding with fasteners driven through it into the wall, and the rails of the final bay are tied into that board. Some builds set a post close to the wall and fasten it to the siding as well, so the post and the wall share the work of holding the end.
At the free-standing end, the run finishes at a post on its own footing, set like every other post in the line. The rails stop at that post. The boards can carry on a short way toward the house so the line reads as closed, but nothing touches the siding, and a small gap stays open between the last board and the wall.
Either end can look tidy from the yard. The difference sits where you cannot see it: whether metal passes through your siding, and whether wood from the fence stays pressed against the house.
Fastening to the Wall: Siding, Sheathing and the Water Behind Them
Siding sheds the bulk of the rain at its face, but it is a cladding, not a watertight skin. Some water gets behind it at laps, seams, and trim. Behind the siding, a water-resistive barrier over the sheathing forms the drainage plane that carries that water down and out. Every fastener that holds a fence board to the wall passes through the siding and that barrier on its way to the framing. Unless each hole is flashed and tied into the drainage plane, water running down the wall can follow the fastener into the wall and reach the sheathing, where no one sees it.
The board itself adds a second problem. Wood siding stays sound because it dries out after each wetting, preventing decay from taking hold. A board fastened flat against it slows that drying. Water that soaks into the contact line between the fence board and the siding stays there, and wood that stays wet long enough decays on both the fence side and the siding side. The board also hides the spot, so the first sign may be a soft patch that appears only when the fence comes off.
Then comes movement. The fence stands on posts in the soil, and the house stands on its foundation; the two do not move together. Every push on the fence, from wind on a solid privacy panel or a dog jumping at the boards, is passed to the wall through the fasteners. Where the air is humid, the fence boards and the end post take on moisture and give it back with each change in the weather, and that cycling can loosen the fasteners over the years, widening their holes in the siding. A fence standing in drier air goes through less of that swelling, so its fasteners stay tight for longer, though the holes and the damp contact line remain.
A Hidden Path for Termites at the Joint
Subterranean termites live in the soil and reach wood that touches it. A fence post sits in the ground so that it can be reached straight from the soil, and damp wood at the ground line gives it everything it needs in one spot. When the run is fastened to the house, the fence becomes a continuous line of wood from the soil to the wall, and the joint behind the fastened board is out of sight. Soil contact at one end and a covered joint at the other give termites a way into the house that nobody sees.
A free-standing end post breaks the wood contact with the wall. Termites can still reach the post, as they can reach any post in the run, but the fence no longer hands them a covered route into the siding, and the gap leaves the foundation and the bottom of the siding at that spot open to view. That does not protect the house on its own, since a fence that hugs the foundation still shelters a strip of damp soil beside it. If anything at the joint looks wrong, a pest-control company should inspect it.
The Free-Standing End Post and Its Small Gap
The free-standing end carries itself. Its post is set in concrete like the rest of the line, its rails are screwed to that post, and the fence's loads go into the ground at the post, not into the wall. The small gap left at the house lets the fence and the house move on their own, so neither one tears at the other when the ground, the wood, or the wind shifts them.
The gap also lets the joint dry. With air on both sides of the last board and nothing pressed to the siding, water running down the wall drips past, and both surfaces dry out after rain. Water at the base matters too. Soil beside a foundation that stays wet draws termites, so a downspout that empties right at the end post, or a hose bib that drips there, is worth redirecting before the fence closes that spot in.
Setting a post near a house has its limits. A concrete apron, poured concrete spreading out from the foundation, a buried line where a service enters the house, an air-conditioning pad or a meter can each push the post a little farther from the wall than you might want. The post goes wherever the ground allows, and the last boards run toward the house to close the line.
Future Siding, Paint and Wall Work
A wall with a fence fastened to it is harder to work on later. Re-siding, painting, or repairing the wall behind the fence means taking the fence end off first, and the fasteners leave holes in whatever siding stays. The strip of siding hidden under the fastened board has not seen sun or weather, so when the board comes off, it can show a different color from the wall around it, and any damage behind it shows up at the same moment, in the middle of someone else's job.
A free-standing end leaves the wall alone. A painter or siding crew works the face of the wall behind the gap without touching the fence. A very narrow gap still makes a brush awkward to reach, so if a full paint job or new siding is coming soon, mention it during the visit, since it can change where the end post is set.
Fastened and Free-Standing Ends Side by Side
The table below puts the two ends against each other point by point.
| Point | Fastened to the wall | Free-standing end post |
|---|---|---|
| What holds the end | The wall, through fasteners in the siding | Its own post in concrete |
| Holes in the siding | One for every fastener | None |
| Water at the joint | Held in the contact between board and siding | Drips past; both faces dry |
| Wood path from soil to house | Continuous, hidden behind the board | Broken by the gap |
| Movement between fence and house | Passed to the wall through the fasteners | Taken up by the gap |
| Seeing the joint | Covered | Open to view |
| Later paint or siding work | Fence end comes off first | Wall is worked behind the gap |
What the Crew Looks at on the Visit
The crew walks the wall where the fence will end, then decides how the run meets the house. These points decide it:
- The siding: What the wall is clad in, its condition at the height of the rails, and whether an old fence was ever fastened there.
- The ground at the wall: A concrete edge, a spreading footing, or a slab that limits how close a post can go.
- Water at the joint: Where the downspouts empty, whether the soil there stays wet, and whether a hose bib or condensate line drips onto the spot.
- What sits on the wall: Meters, vents, an air-conditioning unit, and the places lines enter the house.
- Who works on that wall next: Planned painting, new siding or a window replacement near the fence line.
- How the run lines up: Where the last full bay lands against the wall, which sets how far the end boards have to reach.
Before the visit, stand at the spot where the fence will meet the house during a rain and watch where the water from the roof and downspout lands. A puddle at that spot is worth pointing out to the crew.
If an old fence is coming off a wall it was fastened to, the holes and anything found behind the old board are a matter for whoever handles your siding, and worth knowing about before the new fence goes up.
Do not pry a fastened fence board off the siding to look behind it. The board can tear the siding it is screwed through, so the fence crew takes the end off and a siding contractor judges the wall behind it.
The end of a run is the one place a fence touches the house, and the house is what you keep longest. A joint that stays dry and open to view needs nothing from the wall. A fastened joint ties the fence's water, movement, and insects to the house for as long as the two stay joined.
Frequently Asked Questions
How high does the house's own siding sit off the soil, and does the fence change that?
Wood siding, door frames and window frames should sit at least six inches clear of the ground, which keeps soil, its moisture and its termites off the wall's wood. A fence board fastened to the siding and running down toward the soil bridges that strip, while a free-standing end with a gap leaves it clear.
Do termites have to chew through fence wood to use it as a path?
No. They can build pencil-wide mud tunnels up the face of a post or a foundation and travel inside them, out of the light. They also get into pressure-treated wood through cracks and cut ends, so treated lumber alone does not close the path.
Can wood that stayed wet behind a fastened board dry out and recover?
Decay fungi need wood to remain at roughly 20 to 25 percent moisture for an extended period. Once the water source is gone and the wood dries below that, the decay stops spreading, but the fungus goes dormant in the wood and can start again if the wood gets that wet again. Whether a softened siding board stays or goes is a call for whoever handles your siding.
Should the gap at the wall be caulked shut?
No. Caulk across the gap ties the fence back to the wall it was set free of, and loading siding with extra caulk can trap moisture and block the drainage behind it, the opposite of what the gap is there to do.
Can a small dog slip through the gap at the house end?
It can if the gap is left wide. The last board can be cut to follow the siding profile, so it stands close along its entire height without touching, and the opening left is narrow from top to bottom. Mention a small dog on the visit so the end is sized with it in mind.
Does a brick wall change the choice?
It can. A brick-veneer wall has small weep openings along its bottom course that let water drain out of the air space behind the brick, and a board fastened flat over them can block that drainage. A free-standing end leaves the weep openings clear.
Plan how your fence meets the house — a look at the wall, the siding and the water at the joint settles which end suits your run. Crusberg Fence serves Yorktown and the Virginia Peninsula. Call (757) 508-0538.