THE PRINCIPLES OF A DEEP RETROFIT

Make a plan!

Understand what can be achieved with your house.  Each building is different, so understanding what can and cannot be done from energy efficiency specialists such as Enstall Insulation will guide you through the steps.  We believe there are 3 main areas to focus on:

  1. Maximise the thermal envelope – Wall, ceiling, underfloor insulation, and window upgrades
  2. Implement efficient heating and lighting, and ensure good ventilation
  3. Consider how efficient your appliances are, and see if you can generate electricity

1.  Maximise the thermal envelope

WALL INSULATION
Improve wall insulation – there are numerous options;

Are internal Linings remaining on?  Blow-in cavity wall insulation

Internal Linings removed?  Fresh bulk or blow-in wall insulation with fresh plasterboard installed

External insulation – wrap your house with fresh external insulation, windows and a new cladding

Internal Lining remaining intact and no cavity in the wall to fill?  Fresh insulation to masonry walls, with plasterboard lining

(In New Zealand, external cavity insulation may require building consent)

CEILING/ROOF INSULATION

30%-35% of heat can escape through your roof – so a relatively small investment in roof insulation will deliver great returns.

House with a Ceiling Cavity?  Then fresh bulk insulation, or blow-in insulation

Skillion ceilings? Remove the lining and install either foam board or high-density insulation

Cathedral ceilings with beams?  Inflill the beam-beam cavity with new insulation and fresh plasterboard lining

FLOOR INSULATION

By insulating the underfloor, heat will be retained. Underfloor heating will give a feeling of warmth and comfort underfoot.

Open underfloor area? – Fresh cavity insulation (blow-in of bulk) with a Ground Moisture barrier

For high performance, add insulation to the full thickness of the joists and line with a barrier to maximise performance.

For concrete slabs, externally applied slab edge insulation cn improve performance.

WINDOW UPGRADES

The good, better best approach here is:

  1. Upgrade your windows by adding double-glazed inserts – placing existing glass
  2. Replace your window sashes with new glazing sash units
  3. Replace window sashes and frames with complete units.  This is most effective with external insulation.
LIGHTING in the ceiling

Remove those holes in your ceiling, by replacing older open recessed lights with closed energy efficient LEDs.

DRAFT STOPPING/AIRTIGHNESS

Any gap means the thermal envelope is not working.  Remove gaps around doors and windows.  Look for gaps in your floors and around ventilation.

For higher performance, include vapour control/airtightness systems in the fresh lining, and or consider air-sealing options that now exist in New Zealand.  this can be verified by having a blower door test to assess the air changes in your home

 

2. Implement efficient heating and lighting, and ensure good ventilation

HEATING

Heat pumps are one of the most efficient heating systems for New Zealand typical energy-efficient heating.  These can be installed as single units in individual rooms,  or for improved performance, install ducted systems in your ceiling or under your floors.

LIGHTING

Huge improvements in LED lights have been made in energy-efficient lighting.  Replace any recessed lights with sealed LEDs to remove gaps.  Replacing older incandescent lights will save power.

VENTILATION

 

The good, better best approach here is:

  1. Install extraction fans in your kitchens, bathrooms and laundry, removing that moist air
  2. Install simple heat recovery ventilation units in walls, this becomes important once the house is more air-tight after draft stopping
  3. For high-performance, install a heat recovery ducted system that brings fresh air into the home, retaining the energy and removing stale moist air.

3. ENERGY CONSUMPTION AND PRODUCTION

Appliances

Replace older appliances with more efficient modern devices

Energy Production

Solar panels are the most common system available in New Zealand.

 

A deep retrofit can be a great investment for your home.  Not only will it make your home more comfortable, but it can also help future-proof your home against rising energy costs and climate change. To learn more about Deep Retrofit and how it can benefit your home, contact us today. We answer all your questions and we will set you on the path to a more comfortable and energy efficient home.