Feather edge fencing (also known as closeboard fencing) can look smart for years, but only if it is assembled correctly and properly supported. If you are working out how to install feather edge fencing around your garden, the job is less about speed and more about carefully setting out, using the right materials, and getting each stage right before moving on.
Using posts, timber or concrete, mortised for your chosen feather edge and overall fence height, can make planning and assembling your new fence much easier. Another advantage of using mortised posts is that the finished fence is only as deep as the fence post, which is particularly important when fencing a smaller garden.
Feather edge fencing is a popular choice for securing back gardens, paddocks and boundary lines because it is strong, repairable and promotes privacy for both modern and traditional properties. It also gives you flexibility. You can build it to the height you need, choose timber or concrete posts, and replace individual components later without taking down the whole run. That said, a feather edge fence is built piece by piece, so poor spacing or rushed post installation tends to show up.
What makes feather edge fencing different?
Unlike a fence panel system,feather edge or closeboard fencing is constructed on site using mortised posts, arris rails, gravel boards and vertical feather edge boards. That means more labour, but it also means a stronger finish on awkward ground and a better result where boundaries are not perfectly square.
For most homeowners, that extra work is worth it. You get a more continuous, tailored fence line, and if one board gets damaged in future, you can replace it without changing the whole section. For trade installers, it is often the best option for slopes, uneven levels, or longer runs that require a strong, reliable fence.
Before you install feather edge fencing
Start by confirming your boundary line and checking for any shared fence responsibilities. It is also worth checking for underground services before you dig, especially along front boundaries or near outbuildings.
Then measure and mark out the run properly on the ground. Post centres are commonly set at around 2.4m or 3.0m, but the exact spacing depends on the length of your arris rails and the site layout. When laying out, if you can, adjust your bay sizes to avoid ending a run with a very small bay at one end. It will look much better when the fence is finished, with, for example, four even-sized shorter bays than three long bays and one very short bay tacked on the end. Small errors at the start can make a lot of difference to the end result.
If the ground slopes, decide whether the fence will follow the slope or be stepped. Feather edge fencing can do either, but the choice affects your post heights, gravel board positions and the final look. If you decide to step down, you need to talk through your plans with your post supplier, as the posts may need to be longer and mortised differently. Concrete posts are not usually suitable for stepping down.
You will usually need mortised fence posts, gravel boards, arris rails, feather edge boards, post mix or dry mix concrete, galvanised nails, cleats to attach the gravel boards and a centre stump.
Choosing the right posts for the job
The first big decision is timber or concrete mortised posts. Unfortunately, the mortise detail on both timber and concrete posts varies from one supplier or manufacturer to another. Be careful when buying posts from different suppliers. If your fence will be a mix of timber and concrete posts, or if you are connecting to an existing fence, it is best to seek advice from your supplier.
Timber gives a traditional look and can be easier to work with on some domestic jobs. Timber posts have mortise details which vary depending on the fence height and specifications. However, specialist suppliers like Crestala Fencing Centre can mortise wooden posts in their workshop to suit any customer requirements, such as the number of gravel boards, feather edge changes, changes in overall fence height, or to match an existing post that has failed.
Concrete mortised posts generally last longer in the ground and are a practical choice where durability matters most. On concrete posts, the mortise details vary by manufacturer and cannot be altered. Concrete posts are not suitable for areas where they could sustain impact damage, as they are susceptible to cracking, which can lead to early failure.
There is no single right answer for every site. If appearance is your main concern, treated timber posts may suit the job well. If you want lower maintenance over the long term, concrete posts and concrete gravel boards can be a sound investment.
Post depth matters as much as post material. As a general rule, 25 to 30% of the post should be below ground. Taller fences need deeper holes and stronger posts. On exposed sites in Kent and along the South East coast, it is sensible to build with the weather in mind, not just using the minimum specification.
How to set out the fence line
Run a string line between your endpoints to establish a straight fence line. Mark each post position carefully and check the measurements twice before digging. Dig holes with care; many fencers tell stories of damaging electric, gas, and sewage pipes.
Installing the posts properly
Dig the post holes first. Hole width and depth depend on the post size and fence height, but they need to be generous enough to allow proper support around the post base. Shallow holes are one of the most common causes of early fence failure. Don't be tempted to shorten a post because digging the post hole is difficult.
Set the first end post plumb and brace it before adding concrete or post mix. Once it is secure, move to the next post and repeat the process, using a string line to keep everything in line. Arris rails are fitted into the mortises before the post is concreted.
Take your time here. If the posts are out, the whole fence will be out. Check for plumb on two faces, check the line, and allow the post mix or concrete to firm up before loading the structure. On longer runs, it helps to keep checking with a level rather than assuming each hole is the same.
Fitting gravel boards and rails
Arris rails are slotted into the mortises. This has to be done before each bay's posts are concreted in place. Most domestic closeboard fencing uses two or three rails depending on fence height, with taller fences needing the extra support.
Once the posts are set, install the gravel boards. These protect the feather edge boards from direct contact with the ground, which helps extend the life of the fence. Timber gravel boards should be pressure-treated and attached to timber posts with wooden cleats, while concrete gravel boards are attached to timber posts with special brackets
For concrete mortised posts, both timber and concrete gravel boards are attached using pronged metal cleats.
The rails need to be parallel to the fence section they support. One of the great things about closeboard with mortised posts is how easily it adapts to changes in terrain, especially on sloping ground. The distance between the rails is already set by the mortises, so providing the post ground levels are set up correctly following uneven ground is relatively straightforward.
How to install feather edge fencing boards
This is the part people usually picture when they think about installing feather-edge fencing, but it only works well if the structure underneath is sound. Start fixing boards at one end and work steadily along the first bay.
Fix each feather edge board vertically to the arris rails using suitable galvanised nails. The thicker edge of one board overlaps the thinner edge of the next, creating the classic closeboard finish. Keep the overlap consistent throughout. If it varies, the fence can quickly start to look uneven. An overlap of 20mm is ok. Do not reduce the number of feather edge by using a smaller overlap, as during hot, dry weather gaps will open up between the boards.
A spacing gauge or a simple timber offcut can help keep the overlap uniform. Check the boards regularly with a level, especially during the first few boards of each section. If you let the line drift early on, it becomes much harder to correct later.
On flat ground, the boards should finish neatly against the gravel board and rise to a consistent top line. Some installers use a top rail or capping for a cleaner finish and extra protection. This is not essential, but it does improve appearance and help shed water away from the board tops.
Finishing details that make a difference
Good feather edge fencing is in the details. Care setting out posts, consistent board heights and spacing, all securely fixed, will add up to a better result. It is also worth checking that no timber is sitting directly in soil or standing water.
If you are using timber components throughout, applying a suitable treatment to cut ends is essential. Factory treatment does a lot of the work, but cut surfaces expose unprotected wood and require protection.
Gates, corners and changes in height need a bit more thought than straight runs. These are the points where extra framing or stronger posts may be needed. It is better to account for that at the start than to try to reinforce it after the fence is built. If you purchase your fencing materials from a reputable supplier like the Crestala Fencing Centre, you will get advice and guidance from the start, and your fencing kit will contain a full set of posts mortised with ends, corners, inters, and gate posts etc. made specifically for your project.
Common mistakes to avoid
Most problems with feather edge fencing come down to three things: weak posts, poor setting out and inconsistent board installation. Posts that are too small or too shallow will struggle in strong winds. A rushed setting out could leave the fence snaking across the boundary. Uneven overlap will spoil the finished look, even if the structure is sound.
Material choice matters too. A cheaper board or undersized rail may save money on day one but cost more in repairs later. For exposed gardens, longer runs, or trade jobs where call-backs matter, it usually pays to build it properly the first time.
When DIY is fine - and when to get advice
A feather edge garden boundary fence using mortised posts is well within reach for a competent DIYer with the right tools and enough time. If the run is long, the ground is very uneven, or the site is particularly difficult, it becomes more of a structural job and less of a weekend project, but still achievable. If you are not fairly fit and competent in handling tools, it is probably best to seek help from a professional.
Good supplier advice makes a real difference. Choosing the right post size, rail length, gravel board type and fixing method can save time on site and prevent expensive mistakes. For customers across Kent and East Sussex, Crestala Fencing Centre regularly helps both tradespeople and homeowners every day match materials to the job rather than buying by guesswork.
A feather edge fence is not complicated, but it does reward care. Build the frame properly, board with care, and the finished fence will do what it is meant to do - stand firm, look good and give you a boundary you do not need to think about every time the wind blows.
More Information about feather edge and closeboard fencing.
For more detailed information on feather edge/closeboard fencing, see the Crestala Helpsheet
Closeboard fencing materials and information for DIY
