Specialists in Warm, Dry, Healthy Homes

Sashtec is a London-based company specialising in internal wall insulation, damp diagnosis, and condensation control.
We focus on solving the underlying causes of cold, damp, and mould — not just covering the symptoms.

Our work is designed to create homes that are:

Warmer
Healthier
More comfortable to live in

At Sashtec, we take a different approach.

How heat is retained within the building

How moisture behaves inside the space

How materials interact with the structure

This allows us to design solutions that work long-term, not just for a season.

A Different Approach to Damp & Insulation

Many properties in London — especially solid-wall homes — suffer from cold surfaces, condensation, and recurring damp issues.
These problems are often misdiagnosed and treated with temporary solutions.

We are not a general building company.

Sashtec is focused specifically on:

Internal wall insulation

Condensation and mould control

Damp-related problems

This focus allows us to deliver a higher standard of work, with attention to detail that general contractors often miss.

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Clean, Considerate Installation

Most of our work takes place in occupied homes.

We understand the importance of:

Keeping the space clean and organised
Minimising disruption
Working respectfully within your home

Our installations are carefully planned and executed with this in mind.

Built on Long-Term Thinking

We believe that proper solutions should last.

That’s why our work is based on:

Correct diagnosis before any installation
Appropriate materials for each property
Systems designed to perform over time

We stand behind our work with confidence.

Serving London Homes

We work across London, helping homeowners and landlords resolve:

Cold walls
Condensation on windows and walls
Black mould
Damp-related issues

Each property is different, and every solution is tailored accordingly.