What is metal lathing and where is it used?

Lathing from metal profile is a frame structure that serves as the basis for fastening facing materials: drywall, plastic panels, siding or insulation. Unlike wooden bars, metal profiles are not subject to rotting, deformation from moisture and temperature changes, which makes it an ideal solution for wet areas (bathrooms, kitchens, swimming pools) and facade works.

In an automotive context, metal sheathing is most often used when body repair — for leveling surfaces before puttying, attaching body kits or interior trim of vans, minibuses and trailers. For example, when restoring rusty areas on GAZelle or UAZ Galvanized sheathing helps strengthen the structure before fiberglass or putty is applied. It is also indispensable when arranging hood boxes or shelves in cargo compartments.

Advantages of metal profiles over wood:

- Service life - up to 50 years without corrosion (when using galvanized or aluminum profiles).

- Fire safety (does not support combustion).

- Precise geometry (profiles do not change when humidity changes).

- Possibility of hidden installation of communications (wiring, pipes).

Types of metal profiles for lathing: which one to choose?

All profiles for sheathing are divided into two large groups: guides (UD, PN) and rack-mount (CD, PS). Their difference is in the cross-sectional shape and purpose. Let's consider the main types relevant for car repair and garage construction:

  • 🔹 UD-profile (PN) — guide, mounted along the perimeter of the surface. Used as a basis for attaching rack profiles. Suitable for creating frames for paneling van walls or garage ceilings.
  • 🔹 CD profile (PS) — rack-mount, inserted vertically into the UD profile. The main load-bearing element of the sheathing. For body work, a reinforced version with metal thickness is often used 0.55–0.7 mm.
  • 🔹 Corner profile (PU) — protects corners from mechanical damage. Used when finishing wheel arches or corners of the cargo compartment.
  • 🔹 Arched profile — flexible, for curved surfaces (for example, body kits on tuned cars).
  • 🔹 Profile for drywall (gypsum plasterboard) — standard, but it’s better to choose for a car galvanized with anti-corrosion coating.

For bodywork, the optimal profile is with perforation - it is lighter and allows you to attach the casing without pre-drilling. But for garage shelves or racks it’s suitable profile without holes (for example, Knauf P112), as it can withstand heavy loads.

📊 Which profile do you use most often?
UD (guide)
CD (rackmount)
Corner
Arched
Other

Calculation of sheathing pitch: formulas and practical tips

The sheathing pitch is the distance between adjacent rack profiles. It depends on:

  • 📏 Sheathing material thickness (for example, for drywall 12.5 mm step - 40–60 cm, for siding - 30–40 cm).
  • 🏗️ Loads on the structure (for shelves in a van, the step is reduced to 20–30 cm).
  • 🔧 Profile type (reinforced profiles allow you to increase the pitch by 10–15%).

Basic calculation formula:

Step (cm) = (Wall length (cm) – 10) / Number of profiles

// where 10 cm is the margin for fastening the outer profiles

Example for a wall length 3 meters (300 cm) with 5 profiles:

Step = (300 – 10) / 5 = 58 cm
Sheathing material Recommended pitch (cm) Profile thickness (mm)
Drywall (GKL) 40–60 0.4–0.55
Plastic panels 30–50 0.4–0.6
Siding (metal) 30–40 0.5–0.7
Plywood/OSB (for shelves) 20–30 0.6–0.9
Insulation (mineral wool) 58–60 (for standard roll) 0.45–0.6
⚠️ Attention: When covering round surfaces (for example, arches on tuned cars) the pitch of the sheathing is reduced to 15–20 cmto avoid deflections. For this they use arched profile or make cuts on a standard CD profile every 5–7 cm.

Mark the wall taking into account the pitch and location of communications |

Check the evenness of the surface with a level (tolerance - no more than 5 mm per 1 m) |

Select fasteners (dowel-nails for concrete, metal screws for the body) |

Cut the profiles with a margin of 1–2 cm for adjustment|

Treat the cut areas with an anti-corrosion compound (for example, Tsinkor-Auto)

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Step-by-step installation of lathing: from marking to fastening

The technology for installing metal profile lathing includes 5 key stages. Let's look at them using the example of wall cladding in a garage or van:

1. Marking and surface preparation

With laser level or a plumb line, draw vertical lines on the wall taking into account the calculated step. Mark the attachment points guide profiles (UD) - they should be located on the floor, ceiling and adjacent walls. For body work, markings are applied metal marker, having previously degreased the surface.

2. Fastening guide profiles

Secure the UD profiles around the perimeter using dowel nails (for concrete) or self-tapping screws (for metal). Mounting step - 30–40 cm. For body use rivets or self-tapping screws with a press washer. Important: place between the profile and the wall sealing tape (for example, Dichtungsband) for noise and heat insulation.

3. Installation of rack profiles (CD)

Insert the CD profiles into the guides and secure them "fleas" (self-tapping screws LN 9–11 mm). To strengthen the structure, use jumpers from the same profile, fastening them every 50–60 cm. In body repair, racks are often duplicated welded frame from the corner 20×20 mm.

4. Laying communications

Before covering, lay the electrical wiring in corrugation, pipes or ducts. In vans they use it for this. clip holders, attaching them to the profiles. Important: all wires must be fixed with a margin of 10–15% for thermal expansion (relevant for cars in hot climates).

5. Sheathing and finishing

Fasten the facing material (plasterboard, panels) to the sheathing. For body work, installation of the sheathing is often followed by putty, primer and painting. When upholstering a van, use vibration-absorbing materials (for example, Splen 3004) between the profile and the skin.

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When installing sheathing in a garage, leave a gap 2–3 cm between the profile and the floor/ceiling for ventilation - this will prevent condensation from accumulating.

Typical installation mistakes and how to avoid them

Even experienced craftsmen make mistakes that subsequently lead to casing deflections, corrosion or squeaks. Here are the most common:

  • 🚫 Using rusty or thin profile (thickness less 0.4 mm). For cars only take galvanized profile with markings CX (reinforced).
  • 🚫 No sealing tape between the profile and the wall. This leads to bridges of cold and condensate.
  • 🚫 Uneven profile fastening ("waves" are more 3 mm by 1 m). Check each stage with a level!
  • 🚫 Savings on fasteners. For example, using conventional self-tapping screws instead "fleas" or body rivet guns.
  • 🚫 Ignoring temperature gaps. In vans, the sheathing must have play 1–2 mm at the joints, otherwise it will move when heated.
⚠️ Attention: When covering metal siding (for example, on a trailer) never attach it close to the profile - leave a gap 1–1.5 mm for thermal expansion. Otherwise, the panels will become deformed after just a year of use.
What happens if profile sections are not processed?

Untreated sections of galvanized profiles begin to rust after 3–6 months due to contact with moisture. This is especially critical for body work, where corrosion can spread to the metal of the car. For protection use:

- Zinc spray (for example, Zinc Rich Primer).

- Anti-corrosion primer (for example, Body 992).

- Adhesive sealant for closing ends (for example, Tytan Professional).

Lathing for insulation: nuances and materials

If the sheathing is mounted under insulation (for example, in a garage or van), then the technology has its own characteristics:

  1. Choice of insulation:
    • 🔥 For garages - basalt wool (for example, Rockwool Light Butts) or expanded polystyrene (if moisture resistance is needed).
    • ❄️ For vans - foil penofol (thickness 5–10 mm) + mineral wool.
  • Sheathing step: must match the width of the insulation (usually 58–60 cm for rolled wool).
  • Vapor barrier: mandatory for mineral wool! Use membrane Izospan B.
  • Ventilation gap: leave between the insulation and the sheathing 2–3 cm for air circulation.

    • An example of a “pie” for insulating a van:

    | Sheathing (6 mm plywood) |
    

    | Ventilation gap 2 cm |
    

    | Vapor barrier |
    

    | Mineral wool 50 mm |
    

    | Sheathing (CD profile)|
    

    | Body (metal) |
    💡

    When insulating a van or garage do not use foam to fill the gaps between the insulation and the profile - it disrupts vapor permeability and leads to condensation. Better use it acrylic sealant (for example, Tytan Euro-Line).

    Tools for working with metal profiles: what do you need to have?

    To install metal profile lathing, you will need a specialized tool. Here is the minimum set:

    Tool Purpose Model example
    Metal scissors Cutting profiles without burrs Knipex 95 32 180
    Cutter (edge bender) Formation of flanging on cuts Matrix 21430
    Screwdriver with attachment Fastening fleas and self-tapping screws DeWalt DCD776
    Laser level Marking and levelness control Bosch PLL 360
    Rivet gun Attaching the profile to the body Novus J-250

    For body work you will additionally need:

    • 🔧 Welding machine (if the lathing is combined with a metal frame).
    • 🔧 Riveter for aluminum profiles.
    • 🔧 Anti-corrosion spray (for example, Liqui Moly Rost-Stop).

    Tip: when cutting a profile never use an angle grinder — it destroys the zinc coating and leaves burrs. The best option is electric scissors or manual cutter.

    FAQ: Frequently asked questions about metal profile lathing

    Is it possible to use wooden blocks instead of metal profiles to cover a van?

    Wood is cheaper, but in a van it quickly rots due to condensation and temperature changes. If you still choose a tree, take larch timber, processed antiseptic for cars (for example, Tikkurila Valtti Expert Base). However, a metal profile is still more reliable - it does not deform and does not require replacement every 3–5 years.

    What sheathing spacing is needed to secure battery boxes in a garage?

    For loaded structures (boxes, shelves), the pitch of the rack profiles should be 20–30 cm, and the thickness of the metal is not less than 0.6 mm. Further strengthen the frame cross members from the same profile, arranging them in a checkerboard pattern. Fasten the sheathing (plywood or OSB) with self-tapping screws in increments 15 cm.

    What is the difference between a profile for drywall and a profile for siding?

    Drywall profile (eg Knauf PS 50×50) thinner (0.4–0.55 mm) and is not designed for external loads. For siding or body work, take façade profile (for example, Alutech FP-60) with metal thickness 0.6–0.9 mm and anti-corrosion coating. Also, the facade profile has additional stiffening ribs.

    Do I need to prime the sheathing before covering the van?

    Definitely! Even a galvanized profile can corrode over time in the places of cuts and fastenings. Use primer for metal (for example, Body 960) or zinc spray. Pay special attention to:

    • 🔹 Places for profile cutting.
    • 🔹 Holes for fastening.
    • 🔹 Profile joints.
    How to attach the sheathing to a rusty body?

    First, clean the rust down to bare metal (with a metal brush or grinder), then treat rust converter (for example, Tsinkar). Attach the profile via rubber gaskets or using riveting rivets with sealant. An alternative is to weld it to the body hairpins (for example, M6) and attach the sheathing to them with nuts.