Great Yarmouth Retrofit – Entry 17

After a long enforced break due to COVID-19, we have recently been very happy to be able to return to site and get to work on finishing the retrofit.

So far progress has been good, we have continued with the window fitting in the individual flats. We’ve also been able to start taking down some of the scaffolding.

Great Yarmouth Retrofit – Entry 16

The first Passivhaus certified windows have arrived on site and the team are now installing these into the individual flats. We look forward to completing all window installation over the next couple of weeks.

We’re also making sure to join the airtightness layer around each window reveal.

After carrying out our thorough checking process, we required the insulation providers to come back onto site to pump the small amount of insulation missed in the roof. After that, we continued installation of the Catnic steel roof, and the team have finished off the eaves detail.

Great Yarmouth Retrofit – Entry 15

We begin this entry by welcoming our Great Yarmouth retrofit partners Oxford Brookes University and Enhabit Limited. It was good to show our partners the nearly finished product and look forward to welcoming them back after the retrofit is complete.


Half of the roof installation is now complete – the whole of the back half is now done and we’re looking to have this completed within the next couple of weeks.


In addition, the Steni-board cladding is now about 60% done around the back, and the Teckwood cladding on the back is roughly 30% complete, and we will be finishing this off next week. We are also looking forward to installing the first Passivhaus windows in the coming weeks.

Finally, it was our pleasure to welcome ITV Anglia to our King Street site recently, to talk about our TCosy retrofit and the greater need for energy efficient retrofits across the country, in the face of a worsening climate emergency. You can find the full story at


Great Yarmouth Retrofit – Entry 14

Installation of the Teckwood and Steni-board cladding has continued apace (with some minor interruptions from Ciara and Dennis!), and now we are about 90% complete with the finish on the front and the gable ends of the building.

The gas flues have been extended to all six flats. The Catnic steel roof has just been delivered to site, which we will be looking to install in the next few days. We’re also getting ready for the Passivhaus windows and doors to arrive on site, which we are planning to install within the next couple of weeks.

Great Yarmouth Retrofit – Entry 13

Over the past couple of weeks, we have been able to start making the King Street building in Yarmouth look less like a building project, and more like a home. The team have begun installation of the Steni board which will serve as the external façade.

A firebreak has been installed in between each floor level around the whole building, in the cavity between the Magply and the Steni board. This is designed to expand in the event of a fire, to prevent it spreading further up or down the building via the cladding.


Lead flashings have been installed on the roof, to make the building watertight in the places where our structural thermal envelope meets the neighbouring building.

Finally for this entry, the team have installed a PVC skirt around the perimeter of the bottom of the building to protect the Damp-Proof Membrane – the Steni board will sit on top of this.


It feels very much like we’re on the home stretch now!


Great Yarmouth TCosy Retrofit – Entry 12

Back from the Christmas break, our team at the Great Yarmouth retrofit have gotten stuck in once again. Over the past couple of weeks, they have managed to finish installing all the Magply board, to create the void around the property

This week, the insulation material arrived, and the team on site have began the process of pumping the insulation into the void. With the insulation going in and most of the other structural work almost complete, the residents should begin to feel the benefits of Passivhaus living!

Around the back of the property, we have begun removing part of the brickwork around the window in the upstairs stairwell in order to install Automatic Opening Ventilation (AOV) – this will help to ventilate smoke and other toxic gases in the unlikely event of a fire, helping to meet fire safety standards in the Building Regulations.

Finally, the team have also been working to finish off the eaves at the back of the building and will be done very soon.


Great Yarmouth TCosy Retrofit – Entry 11

Our team have been working hard on installing the Magply A1 fire-rated board around the property. Still some more to go, so work continues on that into this week.


We have also carried on installing firebreaks on each level of the property, to ensure that Beattie Passive’s higher standard of fire safety is reached.


Finally, as work to install the Magply fireboard was underway, it was discovered that an adjacent property has a fishpond not very far from the wall we were working on. Initial thoughts were to just remove this, however we expect challenges like this to present themselves regularly as we take the TCosy forward, and so are trying to find ways to work our thermal envelope around it.


Great Yarmouth TCosy Retrofit – Entry 10

Another busy couple of weeks at King Street!

The team have started installing the non-combustible fire boards around the building and have also been busy fitting the fire-board around the window reveals. The fire breaks are also going in on each floor level inside the void.

The eaves have been built on the roof. Once the building has been clad with steni-board the gutters and downpipes will be attached.

The Monoflex Radon barrier is being put in place in the trench around the bottom of the building, to wrap around the void down to the foundation of the building.

Finally, all the MVHR units have now been checked and commissioned. The machines have been left turned off until we have pumped the structural thermal envelope with insulation. This is because the MVHR ducting runs within this void and thus currently would be very inefficient without it being fully insulated.

Great Yarmouth TCosy Retrofit – Entry 9

A busy few weeks at the Great Yarmouth Retrofit have seen a number of things come to fruition.

18mm Versapanel has now been installed around all the window reveals throughout the building to enhance fire safety – Having in excess of two hours fire resistance.

The aluminium rails have also been completely installed, and the Magply is also on site and ready to be installed onto the railings. This will create the void into which the insulation will be pumped.

The team have completed decking the roof, and the wraptite membrane has been installed on the roof to make it weather tight. Work has now begun on constructing the gable detail.

Finally, installation of the DPC (Damp Proof Course) membrane has begun, about 150mm above ground-level, to the existing foundations to combat Rising Damp and prevent moisture from entering the property.

Great Yarmouth TCosy Retrofit – Entry 8

Over the last couple of weeks, the team completed  installation of the (MVHR) throughout the building – the main unit in the roof space is complete and now all of the flats are connected to it. We’ve also made sure to make good all the holes required for the ductwork on the outside of the building, blocking them up with concrete, reapplying the Passive Purple, and then putting firestops around the ducting.

The team have also installed the roof joists and have now started to deck them, and the aluminium rails continue to go up around the building, and these will eventually hold the external cladding.

Finally, this week we had visits from Alan Osbourne from Building Control, and Paul Quinney, an independent inspector, and were able to show them the progress we have made on site so far.