For garden fence panels, set posts in 600 mm concrete, run a string line, then fix 1.83 m panels on gravel boards for a straight, durable run.
New boundaries change how a plot looks and feels, boost privacy, and shield delicate beds from wind. This guide walks you through a clean, no-drama install that lasts. You’ll get the right tools, the right layout, and steps that avoid the common pitfalls that lead to wobbly lines and sagging panels.
Putting Up Garden Panels: Tools And Prep
Success starts before the first hole. Measure the boundary, confirm the line with neighbours, and sketch a quick plan. Standard panels are 1.83 m wide, so divide the run by 1.83 to estimate post count, then round up. Add end posts and any corners. Mark positions with spray paint or pegs.
Check rules. In most parts of England, fencing at the back can reach 2 m, but anything beside a highway is usually limited to 1 m. If the property is listed or in a conservation area, extra consent may apply. See the Planning Portal’s page on fences, gates and garden walls for the exact limits and exceptions.
Before digging, scan for buried services. Gas, power, water, or data lines can sit alarmingly close to the surface. The HSE guide Avoiding danger from underground services (HSG47) outlines planning, locating, and safe excavation steps that prevent nasty surprises.
Tools And Materials Checklist
| Item | Why You Need It | Pro Tip |
|---|---|---|
| Panels & Gravel Boards | Create the screen; boards lift timber off soil | Pick rot-resistant boards to keep panels dry |
| Posts (Timber Or Concrete) | Anchor the run | Use 100 mm square posts for 1.8 m panels |
| Fast-Set Post Mix | Locks posts fast | Typical grab in 5–10 min; brace while it cures |
| Post Hole Digger & Spade | Dig neat holes | Keep holes narrow; cone wider at base |
| String Line & Pegs | Guarantees straightness | Pull tight; check for belly along the run |
| Level & Measuring Tape | Keep posts plumb; spacing accurate | Use a post level that straps on |
| Clamps & Packing | Hold panels while fixing | Shims prevent pinch on wet timber |
| Stainless Screws Or Brackets | Fixings that won’t rust | Pre-drill to avoid split ends |
| Saw & Mallet | Trim and seat parts | Rub wax on screws for easier driving |
| Timber Preserver & Brush | Seal cuts and drill points | Treat all fresh cuts before assembly |
| PPE | Eyes, hands, and feet safe | Gloves, boots, and eye protection |
Plan The Line And Levels
Pick the face that will be visually critical from your side and run the string line along that face. The line should sit where the panel faces will end up, not down the centre of the posts. Pull the string tight and lift it clear of ground humps using pegs so it stays dead straight.
Set a datum for height. A gravel board gives a clean base and protects timber from splashback. Use a laser or a water level to set one constant top line. On sloping ground, step the boards in neat increments; small steps look tidy, while random changes draw the eye.
Dig Strong Post Holes
For 1.83 m panels and 1.8 m finished height, use 2.4 m posts. Dig 600 mm deep holes (about 2 ft) with straight sides and a bell-shaped base for extra grip. A handy rule of thumb is around one-third of the post length in the ground, with no less than 600 mm for this height class.
Soil type matters. Light, sandy soil benefits from a wider base; dense clay needs decent drainage so water doesn’t sit around the post. Drop a few stones or a handful of gravel in the bottom to prevent a sump effect.
Set End Posts First
Plant the two terminal posts and make them perfect. Pour a little clean water into each hole, add fast-set mix, then top with water until the powder wets through. Tamp with a stick to drive out air. Work in calm weather so posts don’t drift while the mix cures. Brace in two directions and double-check plumb as the grab phase begins.
Stretch The Line And Set Intermediates
With the terminals braced, re-run the string line. Set the first intermediate post where the next panel edge will fall. Keep the post face kissing the line without pushing it. Concrete one post, skip one hole, then go back for the skipped hole. This leapfrog pattern helps keep the line true without fighting wet concrete at adjacent holes.
Fix Gravel Boards And Panels
Gravel boards go first. Use metal shoes or cleats to pick up the board between posts. Check the step pattern and keep the top edges crisp. With the boards in, drop the first panel, pack it level, and fix with stainless screws or purpose-made brackets. Pre-drill near edges to stop splits.
Keep checking plumb and line after each panel. Timber moves with sun and shade during the day. If a panel is crowned, put the crown up for better water shed. Fit caps on posts to block end-grain moisture.
Spacing, Heights, And Fixings
Standard spacing matches panel width: 1.83 m between posts centre-to-centre when using 100 mm posts, or exactly panel width plus the post thickness if you’re building from scratch. Where runs end short, trim one panel and seal fresh cuts with preserver.
Height rules vary by position. Back gardens often allow up to 2 m, but anything facing a highway (including a pavement) tends to cap at 1 m unless permission is granted. Check the Planning Portal guidance linked above for exceptions such as listed buildings and corner plots.
Recommended Dimensions And Mix Guide
| Fence Height | Post & Hole | Concrete Guide* |
|---|---|---|
| 1.2 m | 1.8 m post; 450–500 mm hole | ~1 bag fast-set per hole |
| 1.5 m | 2.1 m post; 500–550 mm hole | ~1–1.5 bags per hole |
| 1.8 m | 2.4 m post; 600 mm hole | ~1.5–2 bags per hole |
*Bag counts are ballpark figures. Soil, hole shape, and post size change the volume.
Choose Panels, Boards, And Posts
Panel Types
Lap panels are wallet-friendly and quick to hang. Closeboard feels sturdier and handles wind better thanks to vertical boards and strong rails. Tongue-and-groove is smart, quiet in a breeze, and pairs well with a tidy garden plan. Pick pressure-treated timber and inspect for straight rails before you buy.
Gravel Boards
Concrete boards shrug off splashback and give a crisp shadow line. Timber boards look warmer and are easier to trim on site. Either way, the board is cheap insurance that stops the panel sitting in wet soil and rotting from the bottom up.
Post Options
Concrete posts are tough and pair with slotted systems that make swapping panels easy later. Timber posts look softer and take screws and brackets anywhere. For ground contact, pick UC4-rated timber and seal the end grain and any fresh cuts.
Wind, Exposure, And Bracing
Open sites take a beating on gusty days. Shorten post spacing on corners, brace the first two bays of long runs, and avoid continuous sail areas near patios where wind funnels. A tiny amount of rake on posts looks messy, so spend the extra minute with the level before each pour.
Drainage And Concrete Technique
Water pooling around collars shortens the life of timber. Form a slight dome at the top of each footing so rain sheds away from the post. Where clay holds water, pop a small gravel collar around the top to keep mud off the joint. When using fast-set mixes, add measured water first, then the powder, and tamp to drive out air pockets for a solid bond.
Legal Boundaries And Good Neighbour Moves
Boundary lines aren’t always the back of an old fence. Check deeds, talk to neighbours before you set anything in stone, and keep the “good” face outward where custom expects it. Trim any overhang that would project into next door’s space and keep working hours polite.
Waste, Reuse, And Clean-Up
Set up a muck area for spoil and a timber stack for offcuts. Re-use decent earth to backfill low spots in beds. Bag up old fasteners so they don’t end up in tyres. Rinse tools before the concrete cures so they live to fight another day.
Fixings That Last
Exterior-grade, stainless, or coated screws beat bare steel every time. Brackets designed for panel systems save time and keep loads where they belong. Keep fixings away from panel edges to reduce split risk, and use clamps so you can work hands-free.
Protect Timber And Prevent Rot
Factory-treated timber still needs care. Seal every fresh cut, drill point, and notch with a compatible preserver. Keep soil from touching panel edges. A clear, breathable waterproofer or a coloured stain helps shed water and UV. Do a light wash each spring, remove creeping plants that trap moisture, and re-coat on a sensible cycle.
Painting And Staining Tips
Pick a dry spell with mild temperatures. Work in shade to avoid flash-dry lines. Brush into joints and end grain first, then roll broad faces. Two thin coats beat one thick coat. Keep a small pot of the same finish for touch-ups after wind events or repairs.
Common Mistakes And Easy Fixes
Wavy Lines
That’s a string line problem. Pull it guitar-string tight, keep it off the ground, and don’t let posts push it. Sight the run from both ends before concrete goes in.
Leaning Posts
Usually rushed bracing or over-wet concrete. Use measured water with fast-set mix, plumb on two faces, and brace until the grab phase passes.
Panels Sitting In Soil
Capillary splash rots timber. Fit gravel boards and maintain a finger’s gap over paving so water clears freely.
Rusty Fixings
Switch to stainless or heavy-duty coated screws. Cheap zinc fasteners stain timber and snap years too soon.
Quick Step-By-Step
- Measure the boundary, agree the line, and mark post centres at 1.83 m intervals.
- Read local rules, check for services, and plan safe digging.
- Set end posts in 600 mm holes with fast-set mix; brace and check plumb.
- Run a tight string line; place and set intermediate posts using a leapfrog pattern.
- Fix gravel boards to the set posts; keep a clean, consistent step or level line.
- Drop panels, pack level, and fix with stainless screws or brackets.
- Fit caps, treat cuts, and seal any exposed end grain.
- Walk the run; tweak fixings, sight lines, and ground clearances.
Care And Seasonal Checks
Walk the boundary after harsh weather. Tighten any brackets that eased, and re-seat caps. Wash mud off the lower rails and clear leaf build-up behind boards. Where posts sit in heavy clay, check that water doesn’t pond around the collars; top up with gravel if needed.
Every two to three years, clean and re-coat timber. Pick products designed for exterior softwood fencing and follow the data sheet for dry times and re-coat windows. Treat fasteners as consumables on high-wind sites; swapping a few screws now and then is cheaper than a blown-out bay.
When To Use Concrete Or Timber Posts
Concrete posts shrug off rot and grip panels with slotted channels, which makes replacement simple later. They’re heavy, so plan lifts and work in pairs. Timber posts look softer and are easier to trim on site; pick UC4-rated stock for ground contact and seal the end grain religiously.
Budget, Time, And Crew Size
A typical two-person team can set six to eight posts in a day once the rhythm clicks, then hang the same number of panels the next day. Cost lands on posts, boards, panels, and mix. Tools last across projects, so borrow or invest based on future plans.
Wrap-Up: A Straight, Quiet Fence That Stays True
Good groundwork makes the difference. Set deep, plumb posts, keep to a true line, lift timber off the soil, and seal every cut. Follow those habits and you’ll get a tidy boundary that stands square through storms and seasons.