Sound deadening is the layer of material applied to the van's metal panels before insulation and lining. Its job is to reduce panel resonance — the booming, drumming sound that metal panels make when you drive over rough tarmac or when rain hits the roof.
A van without sound deadening is noticeably louder inside than a car or estate. The bare metal panels act as a drum, amplifying road noise, engine noise, and rain. Sound deadening material adds mass to the panels, changing their resonant frequency and reducing the energy transferred as sound.
This guide covers the main butyl-based sound deadening products available in the UK, how to choose between them, how much you need, and how to install them correctly.
Butyl vs Asphalt — The Only Choice That Matters
Sound deadening materials use one of two core compounds:
Butyl rubber — A synthetic rubber compound that stays flexible over its lifetime. Butyl does not harden with age, does not crack in cold weather, and does not give off a strong smell. It is more expensive than asphalt but significantly better for a van build.
Asphalt-based — A bitumen-based compound similar to roofing felt. Cheaper than butyl but has three problems in van builds:
- Asphalt hardens and cracks in cold weather. UK winter temperatures (-5°C) cause asphalt-based deadening to crack and lose adhesion.
- Asphalt emits a strong smell in hot weather. In a van parked in the sun, the asphalt smell can be noticeable inside the living space.
- Asphalt is more difficult to remove if you need to access the panel later (it becomes brittle and separates in chunks, leaving residue).
Recommendation: Use butyl-based products only. The price difference is small (£2-£5 per square metre) and the performance difference is significant.
Product Comparison
Kilmat (Kilmat 80 mil, £30-£40 per 40 sq ft roll)
Kilmat is a butyl-based sound deadening product from the US, widely available in the UK through Amazon. It is 80 mil thick (2mm) with an aluminium foil facing.
Price: £35 for a 40 sq ft (3.7m²) roll. Covers approximately 3-5 panels depending on van size. Weight: 2.5kg per roll (approximately 0.7kg/m²) UK availability: Amazon UK (sold by Kenda and other resellers). Prime delivery available. Adhesion: Strong — requires significant force to peel after 24-hour curing. Works on clean, dry metal. No primer needed.
Pros: Best value butyl product available in the UK. Easy to cut (standard scissors). Conforms to curved panels without heating (unlike some thicker products). The aluminium facing reflects heat (minor benefit). No smell. UK-tested for winter adhesion down to -15°C. Cons: 80 mil thickness is adequate but not the thickest available. For very loud vans (Transit Custom with an engine bulkhead behind the cab), a second layer on the cab bulkhead is beneficial. The roll format is less convenient than sheet format — it can be harder to cut precise shapes. Verdict: The best value sound deadening for a UK van conversion. Buy one roll for a SWB van, two rolls for a LWB van with a high roof.
Noico (Noico 80 mil, £25-£35 per 36 sq ft roll)
Noico is another butyl-based product, slightly cheaper than Kilmat. It is 80 mil thick with aluminium foil facing.
Price: £30 for a 36 sq ft (3.3m²) roll. Weight: 2.4kg per roll. UK availability: Amazon UK, eBay. Adhesion: Good — slightly less aggressive than Kilmat but still sufficient for vertical and overhead panel installation.
Pros: Cheaper than Kilmat by about £5 per roll. Same thickness. Quiet in use (no smell, no cracking). Available with a "liner" option (Noico Red) that is pre-perforated for easier cutting. Cons: The adhesive is less aggressive than Kilmat — in cold UK weather (below 5°C), the material does not stick well and needs a heat gun to activate. Kilmat sticks better in cold conditions. Some users report the edges lifting after 6-12 months in high-temperature panels (near the engine bulkhead). Verdict: A good budget alternative to Kilmat. Buy it if the price difference matters. Use a heat gun during installation if fitting in winter.
Silent Coat (Silent Coat 2mm, £35-£50 per 4m² pack)
Silent Coat is a UK brand (made in Germany, distributed by the Silent Coat UK company). It is 2mm thick butyl with aluminium foil facing. It is sold in sheet format (400mm × 240mm) rather than rolls.
Price: £45 for a 4m² pack (42 sheets). More expensive per square metre than Kilmat. Weight: 3.2kg per pack. UK availability: Direct from Silent Coat UK, Amazon UK, eBay, and automotive audio retailers. Adhesion: Excellent — the adhesive is strong and holds well at UK temperatures from -10°C to 60°C.
Pros: The sheet format is easier to work with than rolls — you cut individual sheets to fit each panel section. The adhesive is the most reliable of all tested products. No smell. Silent Coat also sells a closed-cell foam layer (Silent Coat Black Foam, £15/m²) for additional sound absorption. Cons: More expensive than Kilmat (£11/m² vs £9/m²). The sheet format generates more waste on small panels (you cannot unroll a custom length). The sheets are 400mm wide — panels narrower than 400mm require cutting. Verdict: The best product for quality, but more expensive than Kilmat. Use Silent Coat if you want the best adhesive performance and prefer sheet format over rolls. The Black Foam layer is worth adding for the cab ceiling where rain noise is most noticeable.
Dodo Mat (Dodo Mat Deadnix, £35-£50 per 2m² pack)
Dodo Mat is a UK brand (based in Haywards Heath, East Sussex) that specialises in automotive sound deadening and thermal insulation. Their Deadnix product is a butyl-based sheet material.
Price: £45 for a 2m² pack (10 sheets). Significantly more expensive per square metre than Kilmat or Noico. Weight: 2.1kg per pack. UK availability: Direct from Dodo Mat, Amazon UK, specialist car audio retailers. Adhesion: Good — similar to Silent Coat. The product is designed for the UK automotive market and tested for UK climate conditions.
Pros: UK brand with UK customer support. The product is specifically designed for automotive use (not a general construction product rebranded). Dodo Mat also sells thermal insulation (SuperLiner, Thermo Liner) that integrates with the sound deadening. Cons: Very expensive (£22/m² vs £9/m² for Kilmat). The effective area per pack is small — you need 2-3 packs for a full van build, making it significantly more expensive than alternatives. Verdict: Overpriced for a full van conversion. The sound deadening performance is similar to Kilmat at more than double the cost. The thermal insulation products from Dodo Mat are good, but buy Deadnix only if you want the convenience of a single-brand shopping experience.
| Product | Price per m² | Weight | Format | Adhesion | Best For |
|---|---|---|---|---|---|
| Kilmat 80 mil | £9 | 0.7kg/m² | Roll | Very good | Value for money, full van builds |
| Noico 80 mil | £9 | 0.7kg/m² | Roll | Good (needs heat in cold) | Budget builds |
| Silent Coat 2mm | £11 | 0.8kg/m² | Sheets (400×240mm) | Excellent | Quality builds, sheet format preference |
| Dodo Mat Deadnix | £22 | 1.0kg/m² | Sheets | Good | UK brand preference, small areas |
How Much Do You Need?
The standard rule for van sound deadening: cover 50-70% of the metal panel surface area. You do not need 100% coverage. The deadening material changes the panel's resonant frequency — covering 60% of the panel area achieves the same effect as 100% coverage.
Panel area calculation for a LWB high-roof van (Ford Transit, Mercedes Sprinter):
- Roof: approximately 6m² (3m × 2m)
- Side walls (both sides): approximately 8m²
- Rear doors: approximately 2m²
- Cab bulkhead: approximately 2m²
- Floor (if deadening): approximately 6m²
- Total metal surface: approximately 24m²
- 60% coverage: approximately 14.5m² of deadening material
Rolls needed:
- Kilmat 40 sq ft (3.7m²) rolls: 4 rolls (14.8m²) for a LWB high-roof van
- Noico 36 sq ft (3.3m²) rolls: 5 rolls for a LWB high-roof van
- Silent Coat 4m² packs: 4 packs for a LWB van (recommend 3 for walls + 1 for roof)
- Dodo Mat Deadnix 2m² packs: 8 packs (expensive — not recommended)
For a SWB standard-roof van (Vivaro, Transit Custom, Trafic): reduce quantities by approximately 30%. 3 rolls of Kilmat is adequate.
Installation Guide
Tools Needed
- Sound deadening material (Kilmat or chosen brand)
- Scissors or a utility knife with spare blades
- A roller or J-roller (a wallpaper seam roller from B&Q, £5, works well)
- Rubbing alcohol or panel wipe (degreaser)
- Clean cloths
- Heat gun (useful in winter, not essential above 10°C)
Step 1 — Prepare the Panels
Remove all interior trim, headlining, and floor covering. Clean the bare metal panels with panel wipe or rubbing alcohol. The metal must be free of dust, grease, and moisture. If the panels have rust or surface corrosion, treat it with a rust converter before applying sound deadening.
Step 2 — Cut the Material
Kilmat roll: unroll and cut squares or rectangles that fit the panel. Size each piece to fit between the ribs/reinforcements on the panel. A typical piece is 300mm × 300mm. Do not cut pieces wider than the gap between the panel ribs — the material will not contact the metal properly.
Silent Coat/Dodo Mat sheets: cut each sheet to fit the panel contour. The sheet format is easier for this because you can hold the sheet against the panel, mark the cut line, and trim.
Step 3 — Apply
Peel the backing paper. Press the material onto the panel. Use the roller to apply firm pressure, working from the centre outwards to eliminate air bubbles. The roller ensures maximum adhesion — pressing by hand is not enough for long-term bonding.
Step 4 — Cover 50-70% of the Panel
Apply pieces to the largest flat areas of the panel first. Leave the edges and corners (the reinforced sections near panel edges do not resonate as much). The pattern should be: a section of deadening, a gap of bare metal the same width, another section. The alternating pattern is as effective as solid coverage.
Step 5 — Work Your Way Through the Van
Order of application (by priority):
- Cab ceiling (roof above the driver and passenger) — this reduces the rain drumming noise the most
- Cab bulkhead (the metal behind the cab seats) — reduces engine noise transmitted into the living space
- Side walls (the large flat panels) — reduces wind and road noise
- Rear doors — reduces rattle from the door panels
- Roof (living area) — reduces rain noise
- Floor — least important for sound reduction (the insulation and floor covering add enough mass)
Step 6 — Check After 24 Hours
The adhesive cures over 24 hours. After this time, press any edges that may have lifted (usually around curves). If edges lift in cold weather, use a heat gun gently to warm the material and re-roll.
Common Mistakes
Applying over dirty or greasy panels: The adhesive will not bond to oily metal. In 6-12 months, the deadening will fall off the panel and rattle inside the cavity. Clean thoroughly.
Covering 100% of the panel: Unnecessary and wastes material. 50-70% coverage is the accepted standard in the automotive sound deadening industry. The panel ribs provide structural rigidity — the deadening only needs to contact the resonant sections.
Applying over existing factory sound deadening: Some vans have factory-applied bitumen pads (usually in the footwells and cab floor). Remove these first — they are asphalt-based and will crack and smell. They can also hide rust.
Not rolling firmly enough: The adhesive needs pressure to activate. If you press by hand, the material may not stick properly in cold weather. Use a roller. The difference between a hand-pressed panel and a roller-pressed panel is visible within 6 months (the hand-pressed one will have edges lifting).
The Bottom Line
Buy Kilmat 80 mil (£35 for 40 sq ft) for the best value butyl sound deadening in the UK. Buy 3 rolls for a SWB van, 4 rolls for a LWB van. The material is effective, easy to install, and has no smell or cold-temperature issues.
If you prefer sheet format for easier cutting, buy Silent Coat (£45 for 4m²). The sheets are easier to work with on complex panel shapes. The adhesive is the best available.
Do not buy Noico if you are installing in winter (unless you have a heat gun). Do not buy Dodo Mat Deadnix for a full van build — it is too expensive for a similar result.
The most important area to deaden is the cab ceiling. This single panel is responsible for 60% of the perceived road noise in a campervan. Deaden the cab ceiling first, drive the van, and decide if you need to do the rest — you may find the ceiling alone makes enough difference.
