Rainscreen Cladding UK — What It Is, How It Works & Timber Options (2026)

Rainscreen cladding is the standard installation method for exterior timber cladding in the UK — and for good reason. By separating the outer cladding face from the structural wall with a ventilated cavity, a rainscreen system manages moisture far more effectively than any face-sealed approach. Timber that can drain and dry performs significantly better over decades than timber trapped against a damp substrate. This guide covers exactly how rainscreen cladding works, the three main configurations available in the UK — open joint, mixed width, and TIGA secret fix — the timber species and profiles available, and what it costs.

We stock timber rainscreen cladding in Siberian larch, ThermoWood, Nordic spruce, and Douglas fir — browse our full rainscreen cladding range from UK stock with nationwide delivery in 7–14 days. The TIGA concealed fixing system is also available from stock with compatible rainscreen profiles.

What Is Rainscreen Cladding?

Siberian larch rainscreen cladding — vertical boards with open joints installed over a ventilated batten framework. The open joint between boards allows the cavity to breathe and drain effectively at all times.

The term "rainscreen cladding" describes the system and its function rather than a specific product or profile. Any exterior timber cladding correctly installed with a ventilated cavity behind it is technically a rainscreen system. However, in common UK usage "rainscreen cladding" most often refers specifically to the open-joint vertical batten profile — where narrow timber boards are installed vertically with deliberate gaps between them, creating a bold architectural result with exceptional drainage and ventilation performance.

This is the profile most associated with contemporary UK commercial and high-specification residential architecture — the vertical emphasis, open joint rhythm, and natural grain of the timber boards creating one of the most architecturally distinctive exterior cladding systems available in any material. It suits both traditional and contemporary buildings and installs cleanly over virtually any substrate.

The Ventilated Cavity — Why It Matters

External corner detail on a rainscreen cladding installation — the ventilated cavity and batten framework are clearly visible at the corner junction. Correct detailing at corners, reveals, and the base is critical to long-term performance.

The ventilated cavity is the defining performance element of any rainscreen cladding system. It is what separates a rainscreen installation from simply fixing boards to a wall — and its correct specification and detailing is the single most important factor in long-term cladding durability, regardless of species.

In practice the cavity performs three distinct functions simultaneously. It provides a drainage path for any moisture that penetrates the outer cladding layer — water that gets behind the boards runs down the back of the boards and out through the open base rather than pooling against the substrate. It provides an airflow path that allows the cavity to dry between wet periods — the air movement driven by convection through the open base and top of the cavity is surprisingly effective at drying even after sustained rainfall. And it provides a thermal buffer zone between the outer cladding and the structural wall — modestly improving the thermal performance of the facade build-up.

The minimum cavity requirement for standard UK exposure conditions is 25mm clear between the back of the cladding and the face of the breather membrane or substrate. In high-exposure zones — coastal locations, elevated sites, or highly wind-driven rain exposures — a 38mm cavity is recommended to ensure adequate drainage capacity and airflow.

Mixed Width Rainscreen — Design Variation

Siberian larch rainscreen mixed-width cladding — alternating board widths create a more complex visual rhythm than standard single-width rainscreen, adding architectural interest while maintaining the same open-joint performance.

Mixed-width rainscreen cladding uses two complementary board widths installed in an alternating or varied pattern rather than a single consistent width. The result is a more dynamic, less repetitive facade rhythm — the variation in board width creates shadow depth variation and a more considered architectural result than standard single-width rainscreen.

The most popular mixed-width combination in Siberian larch is 90mm and 68mm boards alternated — the wider board provides the primary visual element while the narrower board creates the varied joint spacing that gives the facade its character. Both widths use the same secret fix or face-fix method and install over the same batten framework as standard rainscreen.

Mixed-width rainscreen suits contemporary residential facades, garden offices, and commercial projects where a more refined, considered result is wanted beyond standard equal-width battens. It is particularly effective in Siberian larch — the variation in grain between individual boards at different widths creates subtle tonal variation that enhances the design.

TIGA Secret Fix System — Concealed Fixing for Rainscreen Cladding

ThermoWood vertical rainscreen cladding installed using the TIGA concealed fixing system — no screw heads or nail holes visible on the face of the boards. Download the TIGA technical brochure below for full bracket dimensions and installation specification.

The TIGA facade fixing system is a concealed stainless steel clip-and-bracket system that allows rainscreen cladding boards to be installed with no visible fixings on the face of the facade. Rather than screwing or nailing through the face of each board — which leaves screw heads or filled nail holes visible on the finished elevation — the TIGA system clips each board onto a bracket fixed to the batten subframe via a pre-machined groove in the board edge.

The result is a completely clean face finish — the only visible elements on the facade are the timber boards and the open joints between them. This is the preferred specification on architect-designed contemporary projects where a precise, hardware-free facade surface is part of the design intent. It is also a more durable installation in practice — concealed fixings are not exposed to the UV, moisture cycling, and thermal movement that eventually affects even stainless steel face fixings over decades.

How the TIGA system works — step by step

ThermoWood rainscreen with TIGA concealed fixing — the bracket engages the pre-machined groove in the board edge, holding each board securely with no visible fixings on the face of the finished facade.

The TIGA system is compatible with our ThermoWood TIGA rainscreen 26x68mm, ThermoWood TIGA rainscreen 26x92mm, and Siberian larch secret fix 25x95mm — boards supplied for TIGA installation have the groove pre-machined during profiling. The system requires a TIGA standard bracket pack and a TIGA start clip pack — both available from UK stock.

Timber Rainscreen Cladding — Species Guide

Nordic Spruce Rainscreen — Budget-Friendly Profile Range

Nordic spruce rainscreen 24x68mm — the most affordable timber rainscreen profile in the UK range. Treat with exterior preservative before installation and re-apply every 2–3 years for best performance.

Wider rainscreen board profile — a broader board creates a bolder vertical rhythm with fewer joint lines across the facade, suits larger elevations where a more monumental result is wanted.

Nordic spruce rainscreen cladding is the most cost-effective entry point into the rainscreen cladding system. Available from us in 24x68mm profile from UK stock, it provides all the performance advantages of the rainscreen system at the lowest material cost of any species. The key requirement is regular preservative treatment every 2–3 years — without which untreated spruce in an open-joint rainscreen exposure will deteriorate more quickly than in a closed-board profile, as all four faces of the board are exposed to the elements.

Rainscreen Cladding Profiles — Full UK Range

Rainscreen Cladding for Garden Rooms & Garden Offices

Siberian larch rainscreen cladding on a contemporary UK garden room — the vertical open-joint profile creates a bold, architectural result that sits naturally in the garden landscape and requires minimal maintenance.

Rainscreen cladding is one of the most popular profiles for contemporary UK garden rooms and garden offices — the open-joint vertical boards create a clean, architectural result that sits naturally in a garden setting and performs exceptionally well on the all-four-sides exposure conditions of a freestanding garden structure.

For garden rooms, Siberian larch rainscreen in 20x90mm or mixed-width 90/68mm is the most popular specification — the natural larch grain and weathering characteristics suit the outdoor garden context well. ThermoWood rainscreen with TIGA secret fixing is the premium specification for garden offices where a precise, maintenance-free facade is the brief. For full guidance on garden room cladding options see our garden room cladding guide and garden room cladding cost guide.

Installation Requirements — Rainscreen Cladding UK

Rainscreen cladding installs vertically over a horizontal batten framework fixed to the structural wall. The key installation requirements are:

• Breather membrane over the wall substrate — allows moisture vapour to escape while preventing liquid water ingress behind the batten framework
• Vertical counter-battens fixed through the membrane — creates the ventilated cavity depth and provides the structural fixing substrate for the horizontal battens
• Horizontal fixing battens at regular centres — provides the fixing line for each vertical rainscreen board
• Minimum 25mm clear cavity — between the back of the cladding boards and the face of the membrane
• Open base detail — the cavity must be open at the base to drain. Use a mesh insect barrier to prevent pest ingress without blocking airflow
• Open top detail — the cavity must be open at the top to allow convective airflow. Detail at parapet or soffit must allow air movement
• Minimum 150mm ground clearance — base of the lowest board must be at least 150mm above finished ground level
• A4 stainless steel fixings throughout — for face-fixed rainscreen use A4 stainless ring-shank nails or screws. For TIGA system use the specified stainless clips and screws only
• Seal all cut end grain — apply compatible oil or end grain sealer to every site cut before fixing

For full installation guidance including corner details, window reveals, and base junctions see our timber cladding detail drawings guide and our cladding fixings guide.