Description
The 163 mm base track is the widest standard-gauge aluminium starter profile in the range, sized to accept insulation boards from 150 mm up to 160 mm — the thicknesses specified on deep-renovation, Part L compliance, and near-zero-energy projects. It fixes above the DPC and forms the level shelf that carries the first course of thick insulation around the perimeter.
Where the 163 mm Base Track Performs Best — Deep Retrofit and Compliance Builds
A wall U-value at or below 0.18 W/m²K starts with 150–160 mm of insulation seated on a level base, and the 163 mm base track is the widest standard-gauge starter rail sized to carry it above the DPC at 300 mm centres, subject to calculation. It belongs to the wider insulation fixing accessories range, where each track width is matched to a standard board thickness. On the deepest build-ups, the base rail is where the whole facade line either starts true or starts to drift.
Three project types account for the majority of installations at 150 mm and above, and Renders World holds this profile in stock next-day so a deep spec never waits on the widest starter rail.
- Deep-renovation retrofit — comprehensive energy upgrades where the target U-value sits at or below 0.18 W/m²K, needing 150–160 mm of graphite EPS to close the gap from the existing wall performance, subject to calculation.
- Part L compliance — wall specifications that must demonstrate a U-value satisfying current Approved Document L guidance, where the energy calculation identifies 150 mm as the minimum thickness for the construction.
- Near-zero-energy and Passive House — 160 mm insulation as part of a fabric-first strategy targeting air-tightness and minimal heating demand, often paired with triple glazing and MVHR.
Why Trade Specifiers Choose the 163 mm Base Track
- Widest standard-gauge profile in the range — the 163 mm internal channel covers every thickness from 150 mm Part L boards to 160 mm Passive House specifications in a single starter rail.
- Built for high-performance envelopes — a 160 mm graphite EPS board at lambda 0.032 W/mK typically delivers a wall U-value in the region of 0.16–0.19 W/m²K on standard masonry, subject to calculation.
- Integral drip edge — the formed lower lip projects clear of the wall face, shedding rainwater away from the base zone, which matters more on deep build-ups where the insulation sits further from the substrate.
- Perforated horizontal web — punched apertures let construction moisture escape from behind the boards, maintaining drying capacity in thick assemblies where moisture management is critical.
- Consistent install procedure — fixes at 300 mm centres with standard masonry anchors, cuts cleanly with tin snips, and accepts the same clip-on mesh profile as every standard-gauge track in the range.
Technical Specifications — 163 mm Base Track Data
| Property | Value |
|---|---|
| Profile width | 163 mm |
| Length per piece | 2,500 mm (2.5 m) |
| Material | Aluminium alloy |
| Gauge | 0.6 mm (standard) |
| Finish | Natural mill aluminium |
| Drip edge | Integral lower lip |
| Ventilation | Perforated horizontal web |
| Recommended fixing centres | 300 mm |
| Suitable insulation thickness | 150–160 mm boards |
| Pre-installed mesh | No — clip-on profile required |
How the 163 mm Base Track Compares to Sibling Base Tracks
The standard-gauge base tracks step up in fixed increments to match UK board thicknesses. The 163 mm is the deepest of the family — pick it when the calculation lands at 150–160 mm, and step down where a thinner spec applies.
| Variant | Key Spec | When to Choose |
|---|---|---|
| 93 mm base track | 90 mm boards · 0.6 mm | 9-inch solid brick, Victorian terraces |
| 103 mm base track | 100 mm boards · 0.6 mm | Semi gable ends, north-facing walls |
| 163 mm base track | 150–160 mm boards · 0.6 mm | Deep retrofit, Part L, near-zero-energy |
Where the same 163 mm channel is needed at heavier gauge for multi-storey or system-certified work, the 1 mm heavy-duty 163 mm version carries the same board specification with greater rigidity.
How the 163 mm Base Track Installs Above the DPC
For the best result, establish the datum line around the full perimeter before any track is fixed. A laser level transferred to each elevation, with a chalk reference snapped along the run, keeps the line continuous around corners. The track typically sits about 150 mm above finished ground level and directly above the existing DPC.
Pre-drill at 300 mm centres with a 6 mm masonry bit and fix into the substrate with plugs and screws rated for the masonry being anchored. At 163 mm this is the deepest standard-gauge profile in the range, so the lever arm between the fixing line and the front lip is greater than on narrower tracks, and any looseness at the anchor amplifies as a visible droop at the front edge. Check every fixing for tightness before loading with insulation, and on soft lime mortar place anchors within brick faces rather than joints. Leave a 2–3 mm expansion gap between lengths for thermal movement.
- External corners — mitre-cut both lengths at 45° to keep the drip edge continuous around the return.
- Internal corners — butt one length cleanly into the adjacent wall face and seal the junction with a compatible flexible sealant.
- Adhesive method for thick boards — apply adhesive in a frame-and-dab pattern rather than a full bed, so each board settles onto the shelf without hydraulic resistance from the adhesive layer.
Once the run is verified level, seat each 150 mm or 160 mm board into the channel and embed it firmly into the adhesive, then clip the mesh profile to the front lip ahead of basecoat. Full fixing patterns, anchor placement above the track line, and adhesive coverage rates are covered in the EWI fixings installation guide.
Pro Tips From UK Installers Fitting the 163 mm Base Track
Working at 160 mm changes the project sequence as much as the build-up depth. The track itself is straightforward to fix; the skill on a deep build is coordinating everything that has to step out with it.
- Plan sills, thresholds, and meter boxes before the track goes on — at 160 mm plus basecoat and render the total added wall depth is roughly 175–180 mm, and every existing detail component needs an extension or relocation to clear the new facade line. Handling those once the main-wall boards are bonded is far more disruptive than doing it up front.
- Use the longer fixing plug from the start — 160 mm boards call for a 200 mm fixing plug to achieve the right embedment; order it in volume alongside the boards so the site is not waiting on a second delivery.
- Check the lever-arm risk before loading boards — at 163 mm channel depth, any soft fixing at the back shows as a droop at the front lip once the boards seat into the adhesive, so a quick anchor-tightness check on every length beats re-levelling after the fact.
- Sense-check permitted development before pricing — some local authority designations cap external wall insulation thickness under permitted development, so at 160 mm the build-up may need a planning application; a call to the local planning authority before quoting confirms the route, subject to current guidance.
Is the 163 mm Base Track Right for Your Project?
- Ideal for deep-renovation and compliance-driven projects — choose the 163 mm base track when the thermal calculation specifies 150–160 mm EPS for Part L compliance, near-zero-energy, or comprehensive upgrades targeting wall U-values below 0.20 W/m²K, subject to calculation.
- For standard domestic retrofits at 100 mm — the 103 mm aluminium starter profile suits the thickness most frequently specified on semi-detached and detached properties, with a more manageable build-up depth.
- When a heavy-duty profile is required at 163 mm — the 1 mm heavy-duty 163 mm version offers greater rigidity for multi-storey facades, exposed sites, or certifications specifying a thicker starter rail.
- Pair with matched boards and fixings — order alongside 160 mm boards from the graphite EPS insulation boards collection, or with 160 mm slabs from the Rockwool mineral wool range where an A1 fire-rated layer is specified.
FAQ — 163 mm Base Track Coverage, Compatibility, Ordering
Is the standard 0.6 mm gauge sufficient for 160 mm boards?
On domestic two-storey projects with normal exposure, the 0.6 mm gauge supports 160 mm EPS adequately. The insulation is additionally secured by mechanical fixings above the track line, so the track's primary role is alignment and base support rather than carrying wind load on its own. On multi-storey facades or highly exposed sites where the system designer specifies a heavier gauge, the 1 mm aluminium version of this track is a direct replacement at the same 163 mm width.
What mechanical fixing length is needed for 160 mm insulation?
A 200 mm fixing plug is the standard selection for 160 mm boards, providing the insulation-thickness penetration plus minimum substrate embedment. On substrates with lower pull-out resistance, such as aerated block or soft lime-mortar brickwork, a longer plug or resin anchor may be required to reach the specified holding value. Confirm the fixing length against the system designer's schedule rather than applying a general rule of thumb across the site.
How does 160 mm insulation affect planning and building control?
Adding 160 mm of insulation plus basecoat and render increases the wall depth by roughly 175–180 mm, which can affect building lines and boundary setbacks. Under current permitted development rights, external wall insulation generally does not require planning permission on most dwelling types, subject to conditions such as not projecting beyond the principal elevation and not exceeding certain thresholds in some designations. At 160 mm the build-up may exceed permitted development limits in particular local authority areas, on listed buildings, and in conservation areas. A check with the local planning authority before work begins confirms whether a planning application is required, subject to current guidance.
Can the 163 mm track carry 150 mm boards as well as 160 mm?
Yes. The 163 mm channel accommodates boards from 150 mm to 160 mm. A 150 mm board sits with around 13 mm of front-to-back clearance, taken up by the adhesive bed behind, and still rests on the horizontal shelf while the adhesive cures. Where both thicknesses appear on the same project — common when an assessor specifies different depths on different elevations — the 163 mm profile carries both without switching starter rails.
How many 163 mm tracks does a typical deep-renovation project need?
A deep-renovation retrofit on a semi-detached or detached property typically covers two to four elevations, with combined runs of 20–28 metres depending on house size. Eight to twelve 2.5 m lengths cover most jobs with trimming allowance, plus one or two spares for mitre waste at external corners, bay returns, and any step changes in DPC height where the run drops to a new datum.
Can the 163 mm track carry mineral wool slabs as well as EPS at this thickness?
Yes. The 163 mm channel accepts any 150–160 mm rigid insulation, including mineral wool slabs where an A1 fire-rated layer is specified. Mineral wool is denser than EPS, so dead load per linear metre is significantly higher at 160 mm. On standard two-storey domestic work the 0.6 mm gauge supports it without difficulty; on taller or more heavily loaded facades, consult the system designer on whether the heavy-duty 1 mm version of the 163 mm profile is required.