Timber Windows and Exterior Doors for Your Home & Business

Why Fenestrum?

25+ years of experience manufacturing high-quality wooden Euro-standard windows, exterior doors, and PSK and HS terrace doors and windows.
20+ years in UK heritage restorations—authentic sash & casement windows and doors, fully compliant.
Competitive factory pricing—no middlemen.
Every piece is finished individually—sanded, primed, sealed, and hand-painted, then topped with a glass-smooth glaze.
Built with Roto Frank AG hardware and Teknos finishes for European reliability.
Engineered, knot-free glulam (laminated timber, quarter-sawn) — warp- and split-resistant, bonded with moisture-resistant adhesives.
Energy-efficient insulated glass units (Uw down to 0.5 W/m²K): standard, safety, acoustic, and solar-control options.
78 & 100 mm Euro-profile windows: high thermal efficiency (Uw down to 0.8 W/m²K*) and excellent sound insulation (Class A–A++).
For extra protection from sun, wind, and rain, we add aluminium cladding.
5-year coverage on products and 2-year coverage on hardware, with professional support.
Our Lithuanian factory ensures a transparent process, clear lead times, and timely communication.
See our production process and craftsmanship quality first-hand at our factory.
Built to handle complex projects—with truly personal service.
Corner joints are locked with premium mortise-and-tenon joinery and weather-resistant adhesive for decades of performance.

We are Fenestrum.

For 20 years we have been specializing in the production of wooden windows and exterior doors. We are of ideal size to successfully implement both complex projects and provide exceptional attention and care to each of our individual clients.

We make windows for you with our own hands.

We produce according to individual orders for both individuals and companies. We can provide and implement classic and non-standard solutions for timber windows and doors and we already count thousands of happy customers in Lithuania and the United Kingdom.

Our products

Windows for the European market

Windows for the British market

Terrace windows systems

Exterior doors

"We are distinguished by the attitude to the product we produce, we produce in such a way that the only human resonance about us is a good recommendation."

Aik Kanchinian, Manager

Let's work together.

Even before the signing of the contract, we provide free consultations about products, their use and maintenance, submit pre-project proposals, provide the necessary technical information. We offer you professional and prompt service, ensure the highest quality of products and provide guarantees.

We offer you a professional and responsive service, the highest quality products and guarantees.