A gravel board is one of the simplest ways to protect the bottom of a timber fence panel, but is one actually necessary?
For most new panel fencing installations, using a gravel board is a very sensible choice. It sits underneath the fence panel and creates a barrier between the timber and the ground, helping keep the panel away from soil, damp grass and garden debris.
This is particularly useful in the UK, where the bottom of a fence can remain damp for long periods during autumn and winter.
Gravel boards are available in concrete and timber, with different heights and finishes depending on the fencing system and the finished height you want to achieve.
What Is a Gravel Board?
A gravel board is the horizontal board positioned underneath a fence panel.
Instead of the timber panel extending all the way down to ground level, the gravel board forms the lowest part of the fencing bay.
A typical panel fencing system may therefore consist of:
- Fence posts
- A gravel board at the bottom
- A timber fence panel above it
- Post concrete securing the posts
- Suitable clips or fixings where required
You can browse the current Sky Fencing gravel board range when planning your fence.
Do You Have to Use a Gravel Board?
No. A timber fence panel can physically be installed without a gravel board in some fencing systems.
However, that does not necessarily make it the best installation.
If the bottom of a timber panel sits directly against soil, wet grass or garden debris, it is exposed to much more moisture than a panel raised clear of the ground.
A gravel board creates a replaceable barrier beneath the panel and helps protect the more expensive timber fencing above it.
What Does a Gravel Board Actually Do?
The main purpose is to separate the timber fence panel from the ground.
This can help reduce direct contact with:
- Wet soil
- Grass
- Leaves and garden debris
- Mulch
- Standing surface moisture
- Soil pushed against the boundary
A gravel board also creates a defined base beneath each fencing bay and can make it easier to accommodate small changes in ground level.
Does a Gravel Board Stop Fence Panels Rotting?
A gravel board cannot guarantee that a timber fence panel will never deteriorate.
Timber remains an outdoor material exposed to rain, humidity and natural weathering.
What a gravel board does is remove one particularly undesirable condition: continuous direct contact between the bottom of the panel and the ground.
Keeping the panel clear of soil and accumulated damp debris can therefore help protect the most vulnerable lower section of the fence.
Concrete vs Timber Gravel Boards
Both perform the same basic job, but they create different fencing systems.
Concrete Gravel Boards
Concrete gravel boards are an extremely practical option where durability and low maintenance are priorities.
Sky Fencing's current concrete gravel boards are manufactured from wet-cast, steel-reinforced concrete and are designed to provide a durable barrier beneath compatible fence panels.
Concrete does not suffer from timber rot and is therefore particularly suitable for the part of the fence closest to the soil.
Concrete gravel boards are commonly paired with slotted concrete fence posts.
Timber Gravel Boards
Timber gravel boards maintain a consistent wooden appearance throughout the fence.
They are particularly useful with timber-post systems where the homeowner wants the posts, panels and lower board to visually match.
Because the gravel board itself is timber, it still needs to be treated as an exterior timber component and sensibly maintained.
Which Is Better: Concrete or Timber Gravel Boards?
If your main priority is durability and low maintenance around ground level, concrete is normally the stronger option.
If appearance is more important and you want a completely timber fencing system, a pressure-treated wooden gravel board can be the better fit.
The decision also depends heavily on your posts.
A slotted concrete-post system naturally works extremely well with compatible concrete gravel boards. A timber-post fence gives greater flexibility over the type of lower board and fixing method used.
What Size Gravel Board Do I Need?
Two particularly common concrete gravel-board heights are approximately:
- 6 inches / 150mm
- 12 inches / 305mm
Both protect the panel from direct ground contact, but the height selected affects the overall fence.
Should I Use a 6 Inch Gravel Board?
A 6-inch gravel board is a popular choice when only a modest barrier is required beneath the panel.
One particularly useful combination is:
5ft 6in fence panel + 6in gravel board = approximately 6ft overall fencing height.
This allows you to keep the timber panel clear of the ground while maintaining an overall height around 6ft.
Sky Fencing currently supplies 6-inch concrete gravel boards in different finishes.
When Would I Use a 12 Inch Gravel Board?
A 12-inch gravel board provides a larger concrete section at the bottom of the fence.
A common combination is:
5ft fence panel + 12in gravel board = approximately 6ft overall fencing height.
A taller gravel board can be useful where you want more concrete at the base of the fence or where the layout and ground levels make the additional height useful.
Sky Fencing's current range includes 12-inch plain, recessed and rock-face concrete gravel boards.
Does a Gravel Board Make the Fence Taller?
Yes.
This is one of the most important points to understand before ordering.
The finished fence height includes both the fence panel and the gravel board beneath it.
For example:
- 5ft 6in panel + 6in gravel board = approximately 6ft
- 5ft panel + 12in gravel board = approximately 6ft
- 6ft panel + 6in gravel board = approximately 6ft 6in
- 6ft panel + 12in gravel board = approximately 7ft
This also affects the required post length.
Do not order posts based only on the stated panel height.
Can I Put a Gravel Board Under a 6ft Fence Panel?
Yes, provided the complete system has been designed for the resulting height.
But remember that a 6ft panel installed above a gravel board will produce a fence taller than 6ft.
If your intention is to create a finished fence around 6ft high, using a slightly shorter panel above the gravel board may be more appropriate.
Do Gravel Boards Work With Closeboard Fence Panels?
Yes. Gravel boards are commonly used underneath closeboard panels.
Sky Fencing manufactures our Premium Closeboard Fence Panels in-house in Wickford.
Appropriate Premium panels use 19 overlapping vertical feather edge boards, 47 x 32mm supporting rails, weather capping and 50-micron hot-dipped galvanised nails.
Our Premium Heavy Duty Closeboard Panels use larger 75 x 32mm supporting rails.
Keeping these timber panels raised from direct soil contact with a suitable gravel board helps create a more practical complete fencing system.
Can I Use Concrete Gravel Boards With Timber Posts?
Yes, suitable concrete gravel boards can be used with timber posts when an appropriate fixing or support method is used.
You should check compatibility before ordering because a concrete board does not attach to a timber post in the same way that it simply slots between compatible concrete posts.
Can I Use Timber Gravel Boards With Concrete Posts?
The components need to be checked carefully for compatibility.
Slotted concrete-post systems are particularly well suited to compatible concrete gravel boards because the board can sit within the post slots.
If you want an all-timber appearance, timber posts and timber gravel boards are normally the more natural combination.
Do I Need One Gravel Board Per Fence Panel?
For a straightforward panel fence, each panel bay will normally have its own gravel board beneath it.
So if you have ten standard panel bays, you would generally expect to need ten appropriately sized gravel boards.
Corners, gates, shortened bays and unusual layouts can change the final quantity, so calculate the actual fence layout before ordering.
Can a Gravel Board Be Cut?
Timber gravel boards can generally be cut using suitable woodworking tools.
Concrete gravel boards require suitable masonry-cutting equipment and considerably more care.
Because Sky Fencing's concrete boards are steel reinforced, cutting one is not equivalent to simply shortening a timber board.
Where possible, plan the fencing bays around the standard component sizes before installation.
What About Sloping Gardens?
Gravel boards can be particularly useful on sloping boundaries, but the fence needs to be planned carefully.
Panel fencing is often stepped down a slope rather than following it continuously.
This means the gravel board at the bottom of each bay can also step with the fencing.
Measure each section individually and establish the finished levels before permanently setting the posts.
Can I Bury a Gravel Board?
Part of a suitable gravel board may sit against the surrounding ground depending on the installation and levels.
One of the advantages of concrete is that it is much better suited to this position than the bottom of a timber fence panel.
However, the board and post arrangement still need to be installed correctly and should not be used to compensate for badly planned ground levels.
Which Side of a Concrete Gravel Board Faces Out?
This depends on the design.
A plain gravel board has a straightforward smooth appearance, while recessed and rock-face products have a more distinctive decorative face.
If the board has a decorative face, decide which side of the boundary you want that finish to be visible from before installation.
Plain, Recessed or Rock-Face Gravel Boards?
Once you have chosen concrete, the remaining decision is largely about appearance.
Plain Concrete Gravel Boards
A plain board provides a simple smooth concrete base and works with almost any panel style.
Recessed Concrete Gravel Boards
A recessed face creates a framed appearance and adds more visual detail than a completely plain board.
Rock-Face Concrete Gravel Boards
Rock-face boards have a textured decorative surface designed to create a more distinctive base beneath the fence.
Sky Fencing currently supplies concrete gravel boards in these different styles through our gravel board range. Current product pages confirm both 6-inch and 12-inch options across the range.
Do Gravel Boards Need Maintenance?
Concrete gravel boards are very low maintenance.
They may become dirty or weather naturally over time, but they do not require the same treatment considerations as exterior timber.
Timber gravel boards should be periodically inspected along with the rest of a timber fencing system.
Avoid allowing excessive soil, wet leaves and garden waste to build up against the fence wherever practical.
Can I Add Gravel Boards to an Existing Fence?
Sometimes, but it is not always a simple retrofit.
Adding a gravel board raises the panel, so the existing post length and fixing positions need to accommodate the change.
If the current panels already occupy almost the full usable post height, there may not be enough room to simply insert a gravel board underneath them.
For an existing fence, measure the posts, panels and available space before buying additional components.
Do I Need Gravel Boards With Concrete Fence Posts?
They are a particularly natural combination.
A compatible concrete gravel board sits in the lower section of the post slots and the timber panel sits above it.
This means the components closest to the ground are concrete while the timber panel is raised away from direct soil contact.
For many UK garden fences, this is an extremely practical arrangement.
Do I Need Gravel Boards With Timber Fence Posts?
You do not have to use one, but a gravel board can still provide the same important benefit of separating the timber panel from the ground.
You can choose a timber gravel board for a matching appearance or a compatible concrete board with appropriate supports.
Does a Gravel Board Make a Fence Stronger?
A gravel board provides a defined base to the fencing bay and concrete versions are substantial components, but it should not be treated as a substitute for correctly installed posts.
The stability of the fence still depends heavily on:
- Correct post size
- Suitable post depth
- Correct spacing
- Sound ground
- Appropriate post concrete
- Correctly fitted panels and components
Do I Need a Gravel Board When Replacing One Fence Panel?
If the existing fence already has a sound gravel board, you may only need to replace the damaged panel.
This is one of the useful features of a slotted concrete fencing system: compatible panels and gravel boards are individual components.
Inspect the board before fitting the new panel. If it is cracked, badly damaged or no longer properly supported, deal with that problem at the same time.
What If My Existing Fence Has No Gravel Boards?
If the existing panels are being completely replaced, it is worth considering whether the new fence should be redesigned to include them.
Do not simply add gravel boards without checking the post lengths, because raising the panels changes the overall height and the amount of usable post above ground.
Gravel Boards and Fence Post Length
The gravel-board height must be included when choosing your posts.
For example, a 6ft panel above a 12-inch gravel board creates approximately 7ft of fencing above ground before allowing for installation details.
If you still require a substantial section of post underground, the total post needs to be long enough for both parts of the system.
This is why the panel, gravel board and fence posts should be selected together rather than as separate purchases.
Common Gravel Board Mistakes
Forgetting That It Adds to the Fence Height
This is probably the biggest mistake. A 6ft panel plus a gravel board does not produce a 6ft fence.
Ordering Posts Before Choosing the Gravel Board
Decide the complete above-ground height first, then choose a suitable post length.
Letting Soil Build Up Against the Timber Panel Anyway
A gravel board cannot protect the panel if garden soil or debris is piled above it and directly against the timber.
Buying Incompatible Components
Check that the panel, posts, gravel boards and fixing method form a compatible system.
Ignoring Ground Levels
Slopes and uneven gardens can significantly affect how the lower edge of the fence needs to be installed.
Assuming Concrete Cannot Be Damaged
Concrete is durable but can still chip or crack through severe impact or poor handling. Handle heavy concrete fencing products carefully.
Which Gravel Board Should I Choose?
For many new panel-fence installations, the decision can be simplified:
Choose a 6-inch concrete gravel board if you want a relatively discreet, durable base and the selected panel height works with your required finished fence height.
Choose a 12-inch concrete gravel board if you want a larger concrete section beneath the timber or need the additional height as part of the fencing design.
Choose a timber gravel board if maintaining an all-timber appearance is more important and the board is compatible with your post system.
Choose plain, recessed or rock-face concrete according to the appearance you prefer.
Do I Need a Gravel Board Under My Fence? Final Answer
You do not always have to use a gravel board, but for most new timber panel fencing installations it is a very worthwhile component.
Its most important job is keeping the bottom of the timber fence panel away from direct contact with soil, damp grass and garden debris.
Concrete gravel boards provide a durable, low-maintenance barrier and work particularly well with slotted concrete posts. Timber gravel boards provide similar separation while maintaining a traditional all-timber appearance.
Remember that the gravel board contributes to the total finished fence height. A 5ft 6in panel with a 6in board creates approximately a 6ft fence, while a 5ft panel with a 12in board achieves approximately the same overall height.
Before ordering, choose the complete system together: fence panels, fence posts, gravel boards and post concrete.
Frequently Asked Questions
Do you have to have a gravel board under a fence?
No, but it is usually a sensible addition beneath timber fence panels because it keeps the bottom of the panel away from direct soil, grass and garden-debris contact.
What is the point of a gravel board?
A gravel board creates a protective barrier between the timber fence panel and the ground. It also creates a defined base beneath the fencing bay.
Are concrete gravel boards better than wooden ones?
Concrete is normally preferable where low maintenance and resistance to ground-level moisture are priorities. Timber is useful where you want to maintain an all-timber appearance.
Should I use a 6in or 12in gravel board?
That depends on the desired finished fence height, ground levels and appearance. A 5ft 6in panel plus a 6in board and a 5ft panel plus a 12in board both produce an overall height of approximately 6ft.
Can you put a gravel board under a 6ft fence panel?
Yes, but the gravel board increases the overall height. A 6ft panel above a 6in gravel board creates a fence approximately 6ft 6in high before allowing for site and installation differences.
Can concrete gravel boards be used with timber posts?
Yes, provided appropriate compatible supports or fixings are used.
Can gravel boards stop fence panels rotting?
They cannot guarantee that timber will never deteriorate, but they help by keeping the vulnerable bottom of the panel away from direct contact with damp soil and garden debris.
How many gravel boards do I need?
For a straightforward panel fence, you would normally use one gravel board beneath each panel bay. Gates, corners and shortened bays can alter the final quantity.
Do gravel boards affect fence post length?
Yes. The gravel board adds to the above-ground fence height, so its height must be included when selecting the required post length.
What types of concrete gravel board are available?
Sky Fencing currently supplies plain, recessed and rock-face concrete gravel boards in different heights through the gravel-board range.
Are Sky Fencing concrete gravel boards reinforced?
Yes. Current Sky Fencing concrete gravel-board product specifications state that they are manufactured from wet-cast, steel-reinforced concrete.
Can I add a gravel board to an existing fence?
Potentially, but raising the panel changes the overall fence height. Check that the existing posts provide enough usable height before attempting to retrofit gravel boards.
