How to Build a Fence
Framing square Hammer
All good projects start with a plan, so make sure to lay out your fence on paper before doing anything
else. Most fences in urban and suburban areas will require a building permit. There may be restrictions on height,
construction materials, set backs from property lines and easements. Also, you'll need to check with your utility
company to find out and mark where utility lines are buried. In addition, the deed to your property may be helpful
when determining where property boundaries begin and end. If you aren't positive of these locations, it's money
well spent to hire a surveyor to mark these boundaries.
It's important to determine what kind of fence to build based on your needs. Are you hiding your trash cans
or trying to keep your `Spot' in, or the neighbors `Spot' out? Whatever the thought behind the fence, there's the
saying that " good fences make good neighbors." Which is true if the neighbor gives his approval to your project. No
matter how bitter or sweet the relationship has been, make sure your neighbors agree with your fence layout and designs.
Since a fence may improve your neighbor's property value as well as yours, he may even help physically
and/or financially with the project. Whatever your agreements, write it down for future reference. This may come in
handy when it's time to sell your property
Laying out a line for a fence sounds quite simple and can bebut you must be patient and take it one step at
To begin, install batter boards about 2'-4' beyond the end point of each section of fence line. If the fence
abuts an existing structure, drive in stakes just in front of it (Fig. 1).
Stretch a mason's line between batter boards making sure it's taut. Adjust the string so it reflects your
fence placement. This marks the center of each post.
If the fence will have 90-degree angles, use the 3-4-5 method for making true right angles. On the masons
line, mark out 3 feet from the corner. Then mark on the perpendicular string, 4 feet from the corner. The
diagonal measured from mark to mark should be exactly 5 feet. Adjust the swing on the appropriate string until the
distance between marks is exactly 5 feet. Bingo! You have a true 90-degree corner! (Fig. 2)
The posthole locations are marked on center, that is, from the center of one post to the center of the next
post. To begin marking posthole locations, start with a corner post. Where the two string lines intersect will be the
center of your corner post. Measure along the string line marking each posthole location with masking tape (on the
string). Then use a plumb bob (or a string tied to a rock) to mark the locations on the ground. Mark the spot with chalk
or spray (Fig. 3).
Leave batter boards in place and mark where string now rests
on batter boards. This will give you the ability to check the accuracy of
your post holes after you dig them.
Digging Post Holes
Ideally, the depth of the post holes should be one-half the
height of the post above ground, or one-third of the total post length. But,
this seldom happens. If you're in a frost-free area, you'll average 2 ft.
to 3 ft. in depth. If it's loose sandy soil, try to go a little deeper. If
you're in a freeze area, try to dig the hole below the frost line. On corner
and gate posts, dig these at least to minimum specifications.
It's best to rent a power auger for digging post holes. It's
a 2-person job so have someone help you (Fig. 4).
The holes need to be clean and straight on the sides except
the ones that will be poured with concrete. These holes should have the base
wider than the opening. Try not to dig the hole too wide or break down the
dirt around the hole since the firm dirt is the supporting media for the posteven
if poured in concrete (Fig. 5).
Save the dirt removed from the holesit will be needed
as back fill. You'll have more fill left than used, so plan a place for disposallow
spots in the yard, flower beds, etc. Also, 6" of gravel will be needed
for the base in each hole. The hole should be 6" deeper to make room
for the gravel fill, or if using a flat fieldstone for a base, dig deep enough
to add the rock below the gravel. The gravel is important since this is what
helps drain the water away from the post and eliminates or slows the rotting
of the post. The post should settle about 2" into the 6" gravel
fill, and there should be about a 4" clearance on the sides of the posts
that are poured in concrete.
For posts that are "field set"no concretetry
to keep the hole tight to the sides of the post. If the ground around the
post is firm and stable, then it's that much easier to keep posts plumb after
setting and back filling.
This is the critical part of the project! If the posts are
perfectly plumb and in alignment, the rest of the project will go smoothly.
The fence will stand correctlyno swings or swagsand no extra cutting
and trimming to make pieces fit.
To begin setting the posts, restretch the string lines so
they now indicate the outside surface of the posts. Measure the thickness
of the endpoint and divide by 2, then move your string over to that measurement
Setting posts is a 2-person job. Start with endposts by standing
the endpost in the hole and twisting about 2" into the gravel bed. Add
braces to posts. These need to pivot so use one nail per brace (Fig. 7). Then
using a level, make sure the post is plumb. One person holds post in position
while the other aligns and adjusts. When the post is plumb, fasten the braces
to the stakes. Repeat for all end posts.
When end posts are aligned and braced, stretch another string
line between them about 18" below the top of the posts on the same edge
as the first string line (Fig. 8)
Now, place all remaining posts by aligning and bracing just
as you did the end posts. The bottom string line is meant as a guide but don't
let posts touch the string. If intermediate posts are smaller than end posts
the post shouldn't touch or it wouldn't be centered in the hole (Fig. 9).
When all posts are braced, they're ready to be set.
If you are using posts with mortises or dadoes (or finials
that will be attached later), you will need to set the posts at the correct
height. After you determine how much post you want above ground, measure that
distance from the top of the end post. Fasten a pair of cleats at this point
and position post in hole. Plumb, align and brace, then finish the other end
post (Fig. 10).
Stretch a masons line over the tops of posts until line is
level. Set remaining posts using the same method as end posts.
Concrete & Backfill
By now, you've determined which posts will have concrete
and which will be backfilled. If in doubt, all corner and gate posts should
have concrete, as well as any post that will be in a high wind area or in
loose soil. Make sure the post is set in at least 2 inches of gravel and it's
Once the concrete is mixed, shovel it into the hole. Use
a 2x4 and work the concrete to release any air pockets (Fig. 11). Use a mason's
trowel to form the top with a crown next to the post, as this will drain water
away from the post. The crown can be either above or below the grass level
depending on how you want it to look. If you want to keep the mortared section
of the post free of surface water, let the concrete cure for about 30 days,
then apply a sealing bead of butyl caulk at the base of the post on the concrete.
If the post were caulked every year, the life expectancy
of the post would be extended for a long time.
If backfilling with dirt, each layer or one foot depth of
backfill should be tamped. Overfill the hole with dirt so that you can cap
it, as the extra height will help shed water away from the post (Fig. 12).
An excellent tamping tool is a 6 ft.8 ft. length of
1 ½" galvanized pipe with a cap on the end. A shovel handle, 2"
x 4", or anything else will work, as long as it fits around the posts.
Remember to check for plumb with the level as this is your last opportunity
to make corrections. After the concrete has cured for 24 to 48 hours or the
backfill is in place, the bracing can be removed. If it's not in the way of
the fence construction, it's a good idea to leave the bracing in place for
extra stability until the stringers are installed. It's a judgment call and
certainly not a requirement.
Marking Posts & Installing Rails
Take a look at the elevation sketch you made in the planning
stagehow did you plan to use the post in the fence building? Were they
to be cut off at a certain height and have the rails nailed on top, or are
they to be higher than the infield and have a tapered cut on top to shed water?
First you need to measure your posts for cutting height.
Determine the desired height and measure up from the ground and mark the post.
Fasten a nail at that point and run a chalk line to the other end. Snap a
chalk line (Fig. 13). Make sure all posts are marked.
Mark each post with cutting guides. You'll need to mark around
the entire post. For stepped frames, the chalk line will be angles (Fig. 14).
Cut each post with a power saw. Put yourself in a position
where you can see the mark and comfortably hold the saw for cutting. This
isn't the time to make a mistake and cut a post incorrectly. Use a ladder
if the post is high so you can see the marks and the saw cut.
To add the rails, measure the rail position from the top
of the end posts and position a nail at those points. Run a chalkline between
the end posts and snap it.
For stepped or sloped fences, the rail positions for each
pair of posts must be measured and marked separately (Fig. 15).
Cut the top rails to length by using a measuring tape or
holding in position and marking. When you cut the rail, cut outside of the
mark so the rails form a snug fit.
After the top rails are finished, cut and nail the bottom
Remove any bracing after top and bottom rails are installed.
Ideally, no fence should be on the groundall should
be about 6" above the ground. If a "seal " is required at the
bottom, then a kick board can be installed. The bottom of the fence will be
the first to deteriorate, instead of replacing the entire fence, it's less
expensive and much easier to replace a kick boardif it will blend with
To install a kick board, fasten a 2" x 2" or 2"
x 4" nailer under the bottom rail and fasten the kick board to the nailer.
The kick board can be recessed under the rail so it appears flush and provides
some continuity to the finish instead of just being added on (Fig. 16).
The first thing to do with nail-on infill is to distribute
the infill materials around your fence line so the pieces will be close at
Use a string line as a placement guide for the bottom edges
The nail on infill should have a runner nailed at the bottom
to keep all the boards at the same level (Fig 17). Use a straight 1"
x 3" or 4" fastened to each post with duplex nails. Support the
center with blocking on the ground to keep it level. If the boards have a
finished top, they will line up perfectly after installation.
Start nailing the infill, at a corner, end or gate post.
Nail one board at a time checking every 3-4 feet to make sure infill is plumb
using a level.
When all the boards are in place, mark the cut-off line by
snapping a chalk line between the two end points.
If you're using random length boards, mark the point to cut
above the top rail. Install a runner board to the face side of the fence to
guide the power sawDO NOT try to cut free hand on a chalk line with
a power saw, no matter how good you are with your saw, it won't look as level
as when a guide is used. Do the sawing after all the boards are installed
When installing any style of an infill, use the following
points to help. For butted boards, use your level to plumb every third boardif
variances are caught soon enough they are easy to correct over the next couple
of boards installed.
For angled board installations, make a template28 to
32 degrees, cut out of a large enough piece that it can be slid along the
bottom rail so the new boards can rest against it to keep the angle consistent.
For spaced installations, make a spacer with a cleat to hang
on the top or bottom rail. With consistency comes confidence and speed, and
you'll surprise yourself at how fast the rest of the sections go.
Pre and post construction painting depends on your particular
circumstances. If you have a landscaped area or risk applying paint to your
neighbor's property, set your materials up on saw horses and paint in a safe
area before construction. If you think a drop cloth is all you'll need for
drip and spill prevention, then paint after construction. Even with pre painted
materials, after all the cuts, nails, and hammer blows, it will still require
some touch up, but it won't be such a mess and all the hidden areas will have
a coat of paint applied to help with sealing and preventing water damage.
The term "painting" is used to cover several coatings. Priming and
painting, which can easily blend with the exterior of your home and solid
body stain, which will hide and blend any variances in the lumber. If using
finish grade lumber, a clear stain will highlight the grain and add luster
to the fence project. Regardless of products applied, follow the manufacturer's
directions for surface preparation, pretreatment or primer, and number of
coats for sealing and durability. Your new fence will require regular maintenance
and paintingdon't let it get ahead of youjust remember all the
effort you've expended so far.
Stand back and look, take a deep breathgo ahead and
Building and Hanging a Gate
If your fence will have a gate, make sure to take this into
consideration when planning your fence. Whatever style or size your gate must
be built strong to withstand a lot of wear and tear.
Make sure your gate is wide enough for your specific needs.
If it looks like it will be wider than 4', you'll probably need a double gate.
A single gate can be up to 4'.
Plan the direction that your gate will swing. Most likely
you'll have your gate swing into your yard. It should have about an inch clearance
on the ground.
To build your gate, measure between the posts for the width
of the opening (Fig 19). Subtract the space needed for any hardware, then
cut your top and bottom rails to this length. The frame will probably line
up with the top and bottom rails of the fence.
Cut the frame parts to length. The cross-members will overlay
the upright memberscut them first then fit the uprights in between.
Any special joint preparation should be done at this point.
Assemble the frame by bolting together. You may also nail
together but this will not give as strong of a hold. Make sure to check the
frame for square by measuring the length of the diagonalsthey should
be the same (Fig. 20).
The next step is to add the crossbrace. After marking your
cut lines, cut the crossbrace accordingly at the outside of your mark to give
a tight fit. Drive screws through the crossbrace into the rails.
Cut fence boards to the desired length and attach to the
fence. If there's a space between the boards, make a spacer so the spaces
are equal. Fasten the boards to the top and bottom rails with screws.
Hanging the Gate
Determine where your gate will go and position the hinges
accordingly. Mark the screw holes, then fasten the hinges to the gate.
Position the gate between the posts and rest it on pieces
of wood so that it is at the correct height. Check to make sure that it is
level. Screw the gate to the posts. This is easiest if done by two people.
The latch should be aligned with the center of the gate's
top rail. Mark the screw holes and attach the latch.
A Double Gate
For openings wider than 4', you'll need a double gate. This
is really two single gates equal to the distance between posts minus 1½"-2"
Crossbraces should be installed at opposite diagonals.