You can often put up your own fence next to your neighbour’s fence, provided it is entirely on your land, complies with any planning rules and does not damage or interfere with your neighbour’s property. However, it is not always the best solution. A second fence can improve privacy and appearance, but it can also create maintenance problems, trap moisture and lead to boundary confusion if it is not planned carefully.

The key points are simple: check who owns the existing fence, confirm where your boundary is, keep your new fence on your side, think about the finished height, and speak to your neighbour before work begins. Even if you do not need their permission for a fence on your own land, good communication can prevent disputes.

This guide explains when you can install a fence next to a neighbour’s fence, what to check before starting, how much space to leave between the two fences, and when alternatives such as replacing the existing fence, using free-standing screening or adding planting may be better.

Can I put up a fence next to my neighbour’s fence?

In many cases, yes. If the new fence is fully within your boundary and does not exceed relevant height limits or breach property restrictions, you may be able to install it without your neighbour’s permission.

However, you should not attach anything to your neighbour’s fence, remove it, lean materials against it or build in a way that damages it. The new fence must stand independently on your land.

You should also consider whether a second fence is practical. Two fences placed close together can trap leaves, soil, water and weeds, making both fences harder to maintain.

Check who owns the existing fence

Before installing a second fence, work out who owns the existing one. If the existing fence belongs to your neighbour, you should not alter it, paint it, attach to it or remove it without permission.

Fence ownership may be shown in property documents, but it is not always clear. Do not rely on simple myths such as “you own the fence on the left” or “the posts show who owns it”. These are not reliable rules.

Check:

Your title plan
Property deeds or transfer documents
Any boundary agreements
Previous correspondence with neighbours
Who paid for or installed the existing fence
Information from previous owners

If ownership is unclear, speak to your neighbour before doing any work. Installing a second fence without understanding the boundary can create problems later.

Check the boundary position

The most important practical issue is where your legal boundary sits. The existing fence may not be exactly on the boundary line. It might be slightly inside your neighbour’s land, slightly inside your land or positioned by agreement from a previous owner.

If you are building your own fence, it should be on your land. Do not assume there is enough space just because the current fence faces your garden.

For serious uncertainty, consider professional advice before installing posts. Moving a completed fence is more difficult than checking first.

Can I build right up against my neighbour’s fence?

It is usually better not to build hard up against your neighbour’s fence. A small gap is normally advisable so both fences can dry, move slightly and be inspected.

If two timber fences are pressed tightly together, the space between them can trap moisture and organic debris. This may lead to rot, algae, insect activity and unpleasant smells. It can also make repairs difficult.

A narrow inaccessible gap can become a problem because weeds, leaves and litter may collect there with no easy way to remove them.

How much gap should I leave between two fences?

There is no single gap that suits every situation, but the space should be enough to avoid direct contact and allow some airflow. Where possible, leave enough room for maintenance access, especially if the fence is timber.

When deciding the gap, consider:

Whether you can still clean leaves and weeds from the space
Whether both fences can dry after rain
Whether posts and panels can be inspected
Whether the gap will trap rubbish
Whether animals could become trapped
Whether future repairs will be possible
Whether the gap reduces usable garden space too much

If the space is too narrow to maintain, consider a different solution.

Do I need my neighbour’s permission?

If the fence is entirely on your land, you may not need your neighbour’s permission. However, it is still sensible to tell them what you plan to do.

You will need permission if you want to:

Attach anything to their fence
Remove part of their fence
Lean your fence against their fence
Enter their garden to work
Cut plants growing on their side
Use their fence posts for support
Build directly on a shared boundary

A polite conversation before installation is usually easier than dealing with a complaint afterwards.

Why speak to your neighbour first?

Even if the new fence will be yours and on your land, your neighbour may be affected by the work. They may have concerns about height, light, drainage, damage, access, noise or the appearance from their side.

Explain:

Why you want the new fence
Where it will be positioned
How high it will be
What type of fence panels you plan to use
Whether posts and gravel boards will be included
When the work will happen
Whether access to their side is needed
How you will avoid damaging their fence

They may agree to replace or upgrade the existing fence instead, which could be cheaper, neater and easier to maintain than building a second fence.

Can I attach my new fence to their posts?

No, not without permission. If the posts belong to your neighbour, they are part of their fence. Using them to support your panels, trellis or screening can create extra weight and wind load.

Your fence should have its own posts and supports. It should not rely on your neighbour’s fence for stability.

This is especially important for tall fence panels, privacy screening and trellis with climbing plants.

Can I remove my neighbour’s fence if I build my own?

No. If the fence belongs to your neighbour, you should not remove it without permission. Even if you are installing a new fence on your side, their fence remains their property.

If both fences remain in place, make sure the space between them can be managed. If your neighbour agrees to remove or replace the existing fence, record the agreement in writing.

Can I paint or stain their fence before building mine?

Only with permission. A neighbour’s fence is still their property, even on the side facing your garden. You should not paint, stain, drill or attach anything to it without their agreement.

If appearance is the issue, your own fence or free-standing screen may be a better solution.

Planning rules and fence height

Before installing a second fence, check the finished height. In many domestic situations, fences, walls and gates can be installed without planning permission if they do not exceed usual permitted height limits. These are commonly 2 metres for many rear or side boundaries, and 1 metre where the boundary is next to a highway used by vehicles, including the footpath of such a highway.

Exceptions can apply. Check carefully if the property is listed, in a conservation area, affected by planning conditions or subject to other restrictions.

The finished height includes fence panels, gravel boards, trellis toppers and capping. Do not measure only the panel.

Does a second fence create boundary problems?

It can. A second fence can sometimes make the boundary less clear, especially if future owners are unsure which fence marks the actual boundary.

To avoid confusion:

Keep the new fence clearly on your land
Keep records of why and where it was installed
Take photos before and after installation
Keep any written agreement with your neighbour
Avoid moving boundary markers
Do not remove the neighbour’s fence without agreement

If there is already a boundary dispute, do not install another fence until advice has been taken.

Reasons people put up a second fence

There are several reasons a homeowner may want a fence next to an existing neighbour’s fence.

The neighbour’s fence is low
The fence has gaps
The fence is damaged but not yours to replace
You want more privacy
You want a better-looking boundary on your side
You need a secure garden for pets or children
You want to support climbing plants
You want a consistent fence style around your garden
You want to screen bins, sheds or storage

These are practical reasons, but they do not remove the need to check boundaries, ownership and height.

Privacy benefits of a second fence

A new fence can improve privacy if the existing boundary is low, open or full of gaps. A full-height fence panel, slatted screen or trellis with planting can make a garden feel more enclosed.

However, think carefully before installing a tall fence along the full boundary. If privacy is only needed around a patio or seating area, targeted screening may be better.

Options include:

Full-height fence panels
Slatted fence panels
Privacy trellis panels
Free-standing garden screening
Planter screens
Climbing plants on your own supports
Shrubs or small trees in suitable positions

Security benefits of a second fence

A stronger fence can improve garden security, particularly if the existing fence is low or weak. However, security depends on more than height.

For a secure boundary, consider:

Strong fence posts
Secure panel fixings
Well-fitted garden gates
Reliable gate latches or locks
Removing climbable objects
Good lighting near access points
Keeping sheds and storage secure

A second fence with weak posts or a poor gate will not provide reliable security.

Aesthetic benefits of installing your own fence

One common reason for adding a second fence is appearance. If the neighbour’s fence is old, mismatched or unattractive, a new fence on your side can create a cleaner view from your garden.

This can be useful when creating a more designed space with matching fence panels, timber posts, trellis, planting and gates.

Before choosing the style, consider the rest of the garden. A traditional closeboard fence, modern slatted fence, decorative panel or picket fence will each create a different look.

Problems caused by two fences side by side

Two fences close together can create practical problems if not planned properly.

Possible problems include:

Moisture trapped between fences
Leaves and debris collecting in the gap
Weeds growing where they cannot be reached
Reduced airflow
Rot at the base of timber panels
Animals becoming trapped
Difficulty repairing either fence
Loss of garden space
Confusion over the boundary
Disputes if the new fence damages the old one

A second fence is not automatically wrong, but these issues should be considered before installation.

Moisture and rot between two fences

Moisture is one of the biggest concerns when installing a fence next to another fence. A narrow gap can stay damp because sunlight and airflow are limited. Leaves, soil and moss can collect there, holding water against timber.

This can shorten the lifespan of wooden fence panels and wooden fence posts.

To reduce the risk:

Leave a sensible gap where possible
Use pressure treated timber
Install gravel boards beneath panels
Keep soil and mulch away from timber
Clear debris from the gap if accessible
Avoid trapping climbing plants between fences

Maintenance access between fences

Think about future maintenance before installing the second fence. If the new fence blocks access to the old one, repairs may become harder.

You may need access to:

Paint or stain timber
Remove leaves
Repair posts
Replace panels
Clear weeds
Check for rot
Deal with pests

If the space will be completely inaccessible, question whether a second fence is the best solution.

Animals and gaps between fences

Narrow gaps between fences can trap wildlife or pets. Hedgehogs, birds, cats and other animals may enter the space and struggle to get out, especially if the gap is long, hidden or blocked at one end.

If you create a gap, make sure it does not become a trap. Avoid loose netting, sharp fixings and blocked dead-end spaces.

If wildlife movement is important in your garden, consider whether protecting specific areas with screening is better than closing off the whole boundary.

Installing your own posts

A second fence should be supported by its own posts. Do not rely on the existing fence for support.

Choose posts that suit the fence height, weight and exposure. For full-height privacy fencing, posts must be set securely in suitable holes with post mix or concrete. For lighter screening, post supports may be suitable in some situations, but they are not always appropriate for tall fencing.

Strong posts are particularly important if the fence is exposed to wind.

Timber posts or concrete posts?

Both timber and concrete posts can be used for a second fence.

Timber posts have a natural appearance and are easy to work with. They are suitable for many wooden fence panels, trellis panels and garden screens.

Concrete posts are heavier and more durable. They are resistant to rot and can work well with concrete gravel boards and standard fence panels.

The right choice depends on the space available, desired appearance, fence height, ground conditions and long-term maintenance preference.

Using gravel boards with a second fence

Gravel boards are useful when installing a second fence because they protect the bottom of the panels from damp ground and debris.

They can also help create a neat base line and close gaps under the fence, which is useful for pets and privacy.

Concrete gravel boards are durable but heavy. Wooden gravel boards look more natural but need suitable treatment and maintenance.

Remember that gravel boards add to the finished height of the fence.

What fence style should you choose?

The best fence style depends on why you are adding the second fence.

For privacy

Closeboard fence panels, lap fence panels and privacy slatted panels can all improve screening. A 1.8m fence is a common rear garden privacy height, subject to height rules and site suitability.

For a modern look

Slatted fence panels or horizontal slatted trellis can create a contemporary boundary. These work well near patios and landscaped seating areas.

For decorative screening

Decorative fence panels, lattice panels and trellis panels can soften the boundary and support climbing plants.

For front gardens

Low picket fence panels or decorative low fencing may be more appropriate than tall solid panels, especially near roads or footpaths.

For windy gardens

Hit and miss fence panels or slatted panels may allow more airflow than solid panels, reducing pressure on the posts.

Can I use trellis instead of a full second fence?

Yes, free-standing trellis may be a good alternative to a full second fence. It can provide privacy and plant support without creating a solid double boundary.

Free-standing trellis works well for:

Patio screening
Climbing plants
Softening an unattractive boundary
Creating garden zones
Adding privacy without a full fence run

The trellis should be supported by your own posts and installed on your land. Do not attach it to the neighbour’s fence without permission.

Can I use planting instead of a second fence?

Planting may be a better option if the issue is appearance rather than security. Shrubs, climbers, hedging and small trees can screen an unattractive fence while adding wildlife value and seasonal interest.

Planting options include:

Evergreen shrubs
Climbers on free-standing trellis
Pleached trees where suitable
Bamboo in controlled containers
Mixed border planting
Tall grasses
Climbing roses on independent supports

Choose plants carefully. Avoid species that will become too large, invasive or difficult to control.

Can I install a second fence in a narrow garden?

You can, but it may not be the best use of space. A second fence reduces the usable width of the garden. In a narrow garden, even a small loss of space can be noticeable.

For narrow gardens, consider:

Slatted screening near key areas
Climbing plants on wires or trellis
Paint or stain if the fence is yours
Planters with built-in trellis
A single agreed replacement fence
Targeted screening rather than a full-length fence

A full second fence may feel heavy in a small space.

What if the neighbour’s fence is falling down?

If the fence belongs to your neighbour and is falling down, speak to them before taking action. You cannot usually remove or replace their fence just because it is in poor condition.

If they do not want to repair it, you may be able to install your own fence on your side of the boundary. Make sure your fence is independent and does not rely on the damaged fence for support.

If the fence is dangerous or causing damage, seek advice before doing anything that might escalate the dispute.

What if the existing fence is shared?

If the fence is shared, discuss repair or replacement before building a second fence. A shared replacement may be simpler and neater than two parallel fences.

Agree:

Who will arrange the work
What type of fence will be used
How high the fence will be
Whether posts and gravel boards are included
How costs will be split
Who will maintain it
What will happen to the old fence

Put any agreement in writing. This helps avoid misunderstandings later.

Can I build a fence for pets next to a neighbour’s fence?

Yes, if it is on your land and properly installed. Pet owners often add fencing because the existing boundary has gaps, weak panels or low sections.

For pets, check:

Gaps under the fence
Gaps between the two fences
Gate security
Whether animals can climb or jump
Whether gravel boards are needed
Whether the gap could trap pets or wildlife
Whether the fence is strong enough for the animal

A second fence can help contain pets, but it should not create hidden spaces where animals become trapped.

Can I build a fence for privacy next to a low neighbour fence?

You may be able to install your own privacy fence inside your boundary if it complies with height rules and is structurally sound. This is common where the existing boundary is low, open or not suitable for privacy.

Before doing so, consider whether targeted privacy screening would work better. A full-height fence along the entire boundary may be unnecessary if privacy is only needed around a seating area.

Can I build a second fence next to a hedge?

Yes, but hedges create additional issues. Roots may make post holes difficult, branches may press against panels, and dense growth can trap moisture.

Before installing fencing near a hedge, consider:

Who owns the hedge
Whether it marks the boundary
Whether roots will affect post holes
Whether the hedge contains nesting birds
Whether the fence will be accessible for maintenance
Whether the hedge will push against panels

Do not cut a neighbour’s hedge on their side without permission.

Can I build a second fence beside a wall?

A fence can sometimes be built inside a boundary wall, but it needs careful planning. Posts must be installed without damaging the wall or its foundations.

Do not assume you can fix posts or panels to a neighbour’s wall. If the wall is not yours, permission is needed before attaching anything.

Also check height rules, as a fence installed on or beside a wall can quickly exceed permitted height limits.

Access for installation

Installing a second fence may require access to the boundary. If you need to enter your neighbour’s garden to work, ask permission first.

Do not climb over the existing fence, move their plants or place tools on their side without agreement.

If contractors are involved, tell your neighbour who will attend, when they will arrive and whether access is needed.

Waste and old materials

If you are installing your own fence, you are responsible for your materials and waste. Do not place spoil, old posts, packaging or offcuts in the gap between fences or on your neighbour’s side.

Dispose of treated timber, concrete, nails and fixings safely. Old treated timber should not be burned in the garden.

A tidy installation reduces the risk of disputes and future maintenance issues.

Should you replace the existing fence instead?

In many cases, replacing the existing fence is better than installing a second one. This is especially true if the neighbour is willing to agree and the boundary position is clear.

Replacement may be better because:

There is only one fence to maintain
No hidden gap is created
Moisture problems are reduced
The boundary remains clear
Less garden space is lost
The finished result looks neater
Costs may be shared by agreement

If both neighbours want a better boundary, a single agreed fence is usually the cleanest solution.

When a second fence may be a good idea

A second fence may be suitable when:

The existing fence belongs to the neighbour
The neighbour does not want to replace it
You need privacy on your side
You want a consistent garden design
You can build fully within your boundary
There is enough space for maintenance
The new fence will not damage the existing one
Planning height limits are respected

It is a practical option where handled carefully.

When a second fence may be a bad idea

A second fence may not be suitable when:

The boundary is disputed
There is not enough space
The gap would be impossible to maintain
The existing fence is unstable and could fall into yours
The new fence would block too much light
Height limits may be exceeded
Posts would undermine the existing fence
The garden is already very narrow
Wildlife or pets could become trapped

In these cases, look at alternatives before committing to a full second fence.

Common mistakes when putting a fence next to a neighbour’s fence

Many problems with second fences come from poor planning.

Common mistakes include:

Assuming the existing fence marks the exact boundary
Building partly on the neighbour’s land
Attaching to the neighbour’s fence without permission
Leaving no maintenance gap
Creating a damp, debris-filled space between fences
Forgetting planning height rules
Installing weak posts for tall panels
Not speaking to the neighbour first
Letting plants grow into the gap
Using the gap to dump soil or offcuts
Creating a trap for pets or wildlife
Failing to keep records of the fence position

A second fence should solve a problem, not create a new one.

Checklist before installing a fence next to a neighbour’s fence

Use this checklist before starting:

Check who owns the existing fence
Confirm the boundary position
Decide whether a second fence is necessary
Speak to your neighbour
Check planning height limits
Measure the finished height, including gravel boards and trellis
Leave a practical maintenance gap where possible
Choose suitable fence panels
Choose strong posts
Consider concrete or wooden gravel boards
Check for underground services before digging
Avoid damaging the existing fence
Plan access and waste removal
Consider wildlife and pets
Keep photos and records of the installation

Frequently asked questions

Can I legally put a fence next to my neighbour’s fence?

In many cases, yes, if the new fence is fully on your land, complies with planning rules and does not damage or interfere with your neighbour’s property. Check the boundary and ownership before starting.

Do I need my neighbour’s permission to put up my own fence?

If the fence is entirely on your land, you may not need permission. However, you do need permission to attach to, alter, remove or access your neighbour’s fence or land.

Can I build a fence right against my neighbour’s fence?

It is usually better to leave a gap. Building directly against another fence can trap moisture, make maintenance difficult and increase the risk of damage.

How much space should I leave between two fences?

Leave enough space for airflow and maintenance where possible. A very narrow gap can collect debris and become difficult to clean.

Can I attach my fence panels to my neighbour’s posts?

Not without permission. Your fence should have its own posts and should not rely on your neighbour’s fence for support.

Can I remove my neighbour’s fence if I install my own?

No. If the fence belongs to your neighbour, you should not remove it without their agreement.

Does a second fence count towards planning height limits?

Your new fence must comply with height limits in its own right. Measure the finished height, including gravel boards, trellis and capping.

Is it better to replace the existing fence instead?

Often, yes. If both neighbours agree, one replacement fence is usually neater, easier to maintain and less likely to trap moisture than two parallel fences.

Can I put trellis next to my neighbour’s fence instead?

Yes, if the trellis is free-standing, fully on your land and structurally secure. Do not attach trellis to your neighbour’s fence without permission.

Can a second fence cause damp or rot?

Yes, if the gap between fences traps moisture, leaves and soil. Use treated materials, allow airflow and keep the base clear.

Final thoughts

Putting up a fence next to your neighbour’s fence is often possible, but it needs careful planning. The new fence should be fully on your land, structurally independent and compliant with any relevant height restrictions. It should not damage, lean on or attach to your neighbour’s fence without permission.

Before starting, check ownership, confirm the boundary, speak to your neighbour and think about the practical consequences of two fences side by side. A second fence can improve privacy, security and appearance, but it can also trap moisture and make maintenance harder if installed too closely.

In some cases, replacing the existing fence by agreement is the better solution. In others, free-standing trellis, garden screening or planting may give the privacy you want without creating a double boundary. The best option is the one that improves your garden while keeping the boundary clear, maintainable and neighbourly.