Ashurst 5 – First Fix and Insulation

April 22, 2026

With the structural shell of the new bungalow complete, work moved swiftly onto the first fix stage and fitting of insulation.

First Fix

This phase of a build is a busy, collaborative process, with carpenters, plumbers, and electricians working alongside each other to install the home’s essential services. Timber partition walls were erected, electrical cabling for lighting, sockets, and switches was run, and plumbing pipework positioned – all of which will be hidden from view once the plasterboard goes up.

First Fix Eco Joists

We utilised eco-joists in the construction of the roof – timber joists with open steel webbing that allows services to be easily threaded through. This not only simplifies installation but also reduces both labour time and cost.

Eco Joists

Our timber frame homes are renowned for their energy-saving benefits, and insulation plays a vital role in achieving this. For this project, we laid 150mm of rigid insulation over the damp proof membrane (DPM) at floor level, internal walls were insulated with Rockwool, while external walls and ceilings were fitted with high-performance Actis insulation products.

Insulation

We’ve partnered with Actis for many years, and their systems continue to deliver outstanding results. The effectiveness, speed and ease of installation make Actis products ideal for our custom builds.

Actis Insulation

The innovative heat-trapping honeycomb design of their Hybris insulation ensures every gap between the structural timbers is filled, reducing the risk of thermal bridging. In addition, the reflective vapour control layer (VCL) helps regulate internal temperatures, keeping the property warm in winter and cooler through increasingly hot summers.

From a practical perspective, Actis panels are simple to cut accurately and straightforward to fit, slotting neatly into place. This not only minimises material wastage but can also reduce installation times by up to 30% compared to more traditional insulation methods.

Actis Insulation

By combining thermal performance with airtightness, vapour permeability, moisture resistance, and reflective technology, the Actis system provides a comprehensive and high-performing insulation solution that perfectly aligns with our commitment to building energy-efficient, comfortable homes fit for the future.

To learn more about Actis insulation, please visit our supplier directory.


Frequently Asked Questions

Why is insulation important when building a new home?

High-quality insulation plays a vital role in maintaining comfortable indoor temperatures throughout the year, keeping your home warm in winter and cool in summer. By reducing heat loss and limiting unwanted heat gain, insulation improves energy efficiency and helps lower both heating and cooling costs. A well-insulated home is not only more comfortable to live in, but is also significantly cheaper to run over the long term.

What’s the biggest insulation mistake in construction?

One of the most common insulation mistakes is leaving gaps or poorly fitted sections within the insulation layer. Even small gaps can reduce overall performance by allowing heat to escape and air to leak through the building envelope. Areas around windows, doors, and pipework are particularly vulnerable. Careful installation and continuous coverage are essential to minimise thermal bridging and improve airtightness.

What is thermal bridging?

Thermal bridging occurs when heat passes through a material that is more conductive than the surrounding insulation. Materials like metal or wood can create a continuous path allowing heat to escape more easily, creating weak points in the building envelope, often leading to draughts, cold spots, condensation, and reduced energy efficiency. Common examples include gaps in insulation and poorly insulated junctions around windows and doors.

What is airtightness, and why does it matter?

Airtightness refers to how effectively a building prevents uncontrolled air leakage through gaps, cracks, and openings in the building envelope. An airtight home reduces unwanted draughts by keeping warm air inside during winter as well as preventing excess heat from entering in the summer. This helps maintain stable indoor temperatures, improves comfort and increases energy efficiency.

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