To build a double brick garden wall, set a solid concrete footing, lay two bonded brick skins, and add drainage and caps for strength.
A double brick garden wall gives strong boundaries, tidy edges, and a calm backdrop for planting beds or a patio.
This guide walks you through how to build a double brick garden wall from first sketch to final cap, including materials, footing, brickwork, drainage, and care.
Tools And Materials For A Double Brick Garden Wall
Before you mix a batch of mortar, bring together the tools and materials you need. Having everything ready keeps the build flowing and cuts down on mistakes.
| Item | Role In The Build | Practical Tip |
|---|---|---|
| Bricks | Main structure of both skins of the wall | Pick frost resistant bricks for outside use |
| Cement, Sand, Water | Mixed to form mortar and concrete | Use sharp sand for concrete and soft building sand for mortar |
| Reinforcing Bars Or Mesh | Strengthens the concrete footing | Cut steel so it sits in the lower third of the footing depth |
| String Line And Pegs | Keeps the wall straight and true | Set up the line a brick width away so you can see the face |
| Spirit Level And Square | Checks level, plumb, and right angles | Use a long level for the footing and a short one for each course |
| Brick Trowel And Pointing Trowel | Spreads mortar and shapes joints | Keep trowels clean so mortar bonds well and joints stay neat |
| Wheelbarrow, Shovel, Buckets | Moves and mixes concrete and mortar | Use separate buckets for clean water and for waste slurry |
| Safety Gear | Protects eyes, lungs, hands, and feet | Wear safety glasses, gloves, dust mask, and sturdy boots on site |
Planning Your Double Brick Garden Wall
A solid plan saves time and money once the digging starts. Spend some time on layout, height, and checks before you order bricks and cement.
Checking Rules And Permissions
Before you dig, check local rules on wall height, boundaries, and work beside pavements or shared paths. In the UK, the government publishes clear garden wall safety guidance that shows typical height limits and common risks.
Check where pipes, cables, and drains run so you do not damage them when digging. Mark property lines carefully and talk through the plan with neighbours if the wall sits on or near a shared boundary.
Choosing Size, Layout, And Brick Type
Sketch the length and height of the wall. Mark any corners, piers, or changes in level. A double brick garden wall is usually at least one brick, or about 215 millimetres, thick, with wider sections where gates or changes of direction put more load on the brickwork.
Marking Out The Line And Levels
Bang timber pegs into the ground at each end of the planned wall and run a tight string line between them. Measure back from the string to mark the outside and inside faces of the wall, leaving space for the footing to project beyond the brickwork on both sides, and check levels with a line level or spirit level.
How To Build A Double Brick Garden Wall Step By Step
Once planning is done, you can move on to the practical side of this project. Work steadily, keep checking measurements, and give concrete and mortar time to harden between stages.
Digging And Pouring The Footing
The footing spreads the weight of the wall and keeps it from sinking or tipping. Masonry guides suggest a trench about 600 millimetres wide for a standard double brick wall, with depth chosen so you reach firm subsoil and sit below the local frost line. Retail guides such as the B&Q foundation guide for garden walls show clear sketches of this layout.
Excavate the trench along the marked line, spread and compact a thin layer of hardcore, set up shuttering if the soil is loose, and lay any reinforcing steel on small spacers. Mix concrete, pour it into the trench, tamp it down to remove air pockets, and strike the surface flat with a straight piece of timber and a level. Let the footing cure for at least two full days in mild weather.
Laying Out The First Course
When the footing has hardened, mark the centre line of the wall on the concrete and set out the first course of bricks dry, both skins side by side, to check bond and make sure you can finish with full or half bricks at corners and ends. Set up corner profiles or build short starter piers and use them to carry string lines as you build up each course, checking every corner for right angle with a builder’s square so the two skins stay parallel.
Laying The Two Skins
Spread a bed of mortar on the footing for the first course, about 10 millimetres thick, and butter the ends of each brick so joints fill fully. Work from the corners along the course, bringing the outer and inner skins up together so the wall stays level across its full width. Stagger vertical joints in each skin by half a brick, keep a regular bond pattern, and after every metre or so check both faces with a level and the top with a straightedge, tidying off surplus mortar before it hardens.
Tying The Skins Together
A double brick wall needs the two skins tied together so they behave as one unit. You can do this with metal wall ties set every few courses, or with header bricks laid across both skins at regular intervals. Push metal ties into the mortar joints while they are still fresh, making sure they slope slightly down toward the outer skin so water does not run into the cavity, and keep header bricks level so the face pattern stays tidy.
Adding Drainage Behind The Wall
Water trapped behind a garden wall can build pressure and cause cracking or movement. Many retaining wall guides recommend a gravel backfill band and, where needed, a perforated drain to move water away from the base of the wall. Once the wall reaches about half height, tip a layer of clean gravel between the rear face and the soil. For taller retaining sections, run a small perforated pipe at the base of this gravel band and lead it to a soakaway or a free draining part of the garden, lining the soil side with geotextile fabric so fine particles do not clog the stone.
Capping And Finishing The Wall
A good cap keeps rain off the top course and gives your wall a finished look. You can lay purpose made coping stones with a drip groove on each side, or use a double row of bricks laid on edge with a slight overhang. Lay a rich mortar bed for the cap, set each unit down with a gentle tap of a rubber mallet, keep joints tight and even, and tool the joints below so water sheds cleanly off the face.
Building A Double Brick Garden Wall For Beginners
If this is your first full masonry project, break it into simple stages and give yourself time. The wall does not need to rise in one weekend. Stop when you feel tired and come back with fresh eyes; rushed brickwork shows later in crooked lines and joints.
Simple Safety Habits On Site
Good habits on site keep you and anyone passing by out of harm’s way. Stack bricks so they cannot topple, keep paths clear of offcuts and tools, and do not let children or pets play near open trenches or fresh concrete. Wear gloves when handling bricks and steel, eye protection when cutting bricks with a bolster or saw, and lift with your legs rather than your back.
Typical Double Brick Wall Mistakes
Most DIY double brick walls go wrong in similar ways: rushed footing work, poor bonding between skins, and lack of drainage.
| Problem | Visible Symptom | Better Approach |
|---|---|---|
| Shallow Footing | Wall leans or cracks after heavy rain | Dig to firm subsoil and pour a wider, deeper concrete base |
| Poor Bond Between Skins | Hairline cracks along mortar in one skin only | Add regular metal wall ties or header bricks tying both faces |
| Irregular Joints | Uneven courses and wandering vertical joints | Use a gauge rod and string lines for each course |
| Weak Mortar Mix | Mortar crumbles or washes out quickly | Follow a tested cement, sand, and water ratio for external walls |
| No Drainage Behind Wall | Damp patches, bulging, or efflorescence | Add gravel backfill and a small drain at footing level |
| Exposed Brick Tops | Spalling and crumbling on the upper courses | Fit copings or brick-on-edge caps that throw water clear |
Maintenance Tips For Your Finished Garden Wall
Once the mortar has cured and the site is tidy, a little care each year keeps your double brick wall in good shape. Walk along the wall and look for loose joints, leaning sections, or blocked drainage outlets.
Brush moss and soil off copings so they can shed rain cleanly, and clear leaves and debris from the base of the wall so water does not sit against the brickwork. If you see small cracks in mortar, rake them out to sound material and repoint with fresh mix during dry weather.
Keep large shrubs trimmed or moved so roots and branches do not press on the wall.
By planning carefully, digging a sound footing, tying the two skins together, and giving the wall regular care, you gain the full benefit of all the effort that goes into how to build a double brick garden wall. With those habits, the same method can guide other masonry projects around your plot.