SuperHome Database

Wales, Cardiff, Merlin Close

House Summary

Desi Nikolova and Nik Chochev

House Type:
1982 Detached

Carbon saving:
67% - Remote Assessed  

  • boiler

Measures installed:

  • Condensing boiler
  • External Wall Insulation
  • Floor Insulation
  • Loft Insulation
  • Low Energy Appliances
  • Low Energy Lighting
  • Mechanical Ventilation Heat Recovery
  • Roof Insulation
  • Triple Glazing
  • Underfloor Heating

Upcoming events

Early interest in Open Days encourages SuperHome owners to host more events. If you'd like to visit this property please contact the owner and let them know. SuperHomers are often happy to respond to questions about their refurbishment project by email between times. Please read ‘more on contacting this SuperHomer’ before you make contact.

Personal story:

I (Desi) am an Architect and a Passivhaus Designer and my husband Nik has been very supportive although he has no construction background. We have a son Christopher who was born about a year ago in the middle of our renovation, which has made this project so much more exciting


I couldn’t believe when we first viewed the property that we could be that lucky – it was a detached three bedroom house with a single garage on a corner plot. It had great potential to be extended and because it was in quite poor condition – no heating, old kitchen and very old bathroom, stained carpets – it was cheap. However that is what we wanted a property that we can decorate and renovate ourselves – so we bought it with the idea that we will turn it into a Passivhaus.

Since it needed complete renovation I decided to go the extra mile and prepared a project for extension and of course amended the existing layout so the extension feels like part of the house and not addition to the house. We shortly received planning but we decided to separate the project in two phases:

Phase one – renovate the existing house so we could move in an give up the flat we were renting

Phase two – extend the house

When renovating I planned temporary separating walls between the house and the extension so the disturbance from the building works was minimised.

We have done a great deal ourselves with help from family members especially my father-in-law who works in construction to minimise cost

Property background:

The house was built in the 1980s. It is detached house. It only had one owner and it seemed that the only improvement the previous owners had made was the cavity fill insulation

Key changes made:

  • New Ground floor slab and Under Floor Heating (UFH)
  • New Roof and Loft Insulation
  • External Wall Insulation (EWI)
  • New Boiler
  • Mechanical ventilation with Heat Recovery (MVHR)
  • New triple glazed windows
  • New kitchen with energy efficient appliances
  • New bathrooms with water saving measures
  • LED lighting throughout
  • Airtightness membrane  to roofs

Full details of measures installed

  • New Ground floor slab with 300mm PIR Insulation and Under Floor Heating (UFH) –
  • New 200mm Roof and 200mm Loft Insulation
  • 160mm External Wall Insulation (EWI) and render
  • New Gas Boiler with unvented cylinder with an option to connect Solar thermal at later stage
  • Mechanical ventilation with Heat Recovery (MVHR) from Airflow – heat recovery in excess of 90%
  • New triple glazed windows installed to a Passivhaus Detail
  • New kitchen with energy efficient appliances – A+ or higher
  • Water saving dishwasher and washing machine
  • New bathrooms with water saving measures – Water saving taps, toilets and showers
  • LED lighting throughout
  • Pro Clima air tightness membrane  to roofs
  • Insulated loft hatch
  • Minimum penetrations to the outside
  • Details minimising Thermal bridging
  • New Extension wall – solid wall masonry with lightweight thermal blocks with 160mm EWI
Measures installed in detail:

  • External Wall Insulation
  • Floor insulation
  • Loft Insulation
  • Mechanical Ventilation with Heat Recovery
  • New Gas boiler with unvented cylinder
  • Roof insulation
  • Triple Glazing
  • Under floor heating
Benefits of work carried out:

Great comfort of living.

Lower energy bills.

House that feels ours.

Favourite feature:

MVHR – the ventilation supplies fresh air throughout the house and extracts moisture from the bathrooms and kitchen but it is completely undetectable. You cannot hear it, or feel it – no draughts , no background noise. However I know it is there especially when I tried to steam up the bathroom one time and I couldn’t , because when the sensors in the MVHR detect moisture it goes into boost mode to keep up.

And the other thing I love about the house – no radiators – they waste space and are hot surfaces potentially dangerous for the baby – and I love the fact that we don’t have any.

Contact this homeowner

Assessment types

SuperHomes Assessed

A home that has been visited and assessed by us and confirmed as reaching the SuperHome standard, which demonstrates a 60% carbon saving.

Homeowner Reported

Information has been provided by the homeowner about their home and energy use prior to the installation of measures and following their installation which demonstrates a carbon saving. This information has not been verified.

Remote Assessed

The homeowner has provided information on their home including what measures have been installed which has enables an assessor working on our behalf to assess their carbon savings. This home has not been visited to verify the measures installed.


This home has not been assessed, but the homeowner has reported what measures have been installed. It may be that this home is awaiting assessment.