Home Energy Saving scheme

Home Energy Self Survey

(Complete each section by ticking all boxes where the statement reasonably describes your home)


1. Roof / Attic .

- Does your property have an attic?

HINT: tick the box even if your attic is converted .

- Does more than one quarter of the attic / roof area currently have less than 4 inches of mineral / glass fibre insulation OR less than 2 inches of polystyrene or solid insulation board?

HINT: If your home was built before 1993 and hasn’t been upgraded since, or you don’t know what, if any, insulation is in your attic then tick the box

If you TICKED ALL of the questions above then it is likely that increased attic insulation would be appropriate for your home. The simplest way of doing this in an attic is to roll out fibrous insulation (i.e. glass fibre, rock wool, sheep’s wool, etc.) between the joists with a second layer at right angles above the joists. Alternative materials include blown wool insulation and cellulose fibre, which are blown into place by machine between and over the joists by a contractor. Rigid foam insulation, cut to slot in between the joists, can achieve the same level of insulation as fibrous insulation but with approximately half the thickness because it has approximately double the insulating effect.

  • -Ensure you maintain access to the water storage tank and any other appliances in the attic space
  • -Cold water tanks should be insulated on the sides and on top –typically with no insulation fitted underneath the cold water tank to help prevent freezing
  • -Don’t compress fibrous insulation as this reduces its performance
  • -It is important to ensure adequate ventilation of the attic space above.

2a. Walls (Cavity) .

- Do your rooms feel colder than you feel they should and / or is there the appearance of mould on the walls? . -

- Do you believe that more than a quarter of your exposed walls have little or no insulation?

HINT: Typically if the home was built prior to 1993 then the cavity would be suitable for additional top up insulation. .

- Is the majority of your your property built using cavity wall construction?

HINT: A cavity wall consists of two rows of brick or concrete block with a continuous cavity or space between them. This is different to ‘hollow block’ construction.

If you answered TICKED ALL of the above questions it is likely that blown cavity wall insulation would be appropriate for your home.

A cavity wall consists of two rows of brick or concrete block with a continuous cavity or space between them. Injection of insulation from the outside is the best method for retrofitting insulation in this type of wall.

  • -Contractors must assess the walls and cavities to determine their suitability for pumped or blown insulation. Consideration must also be given to any adjoining properties as this can present particular challenges. If you live in an apartment then it will be necessary to insulate all units in the block.
  • -NSAI Agrément-certified insulation materials for pumping or blowing into cavities are typically made from expanded polystyrene or mineral wool.
  • -The work is done from the outside so there is minimal disturbance.
  • -The holes are then filled to match the external wall appearance
  • -The job should take less than a day to complete.

Fully filling the cavity with a certified insulation will not lead to dampness on the inside of your walls where there are no construction defects such as mortar droppings or poor cavity ties. Where these exist, there is an increased risk of moisture penetration through to the inner leaf, especially in the case of fibrous insulation. The cavity are designed to prevent moisture penetrating from the outer surface of the wall to the inner surface.


2b. Walls (Solid Wall or Hollow Block or Timber Frame) .

- Do your rooms feel colder than you feel they should and / or is there the appearance of mould on the walls? .

- Do you believe that more than a quarter of your exposed walls have little or no internal dry lining insulation?

HINT: If your home was built before 1993 and hasn’t been upgraded since then tick the box .

- Is the majority of your property built of solid walls Or hollow blocks OR timber frame?

HINT: If you didn’t tick for cavity wall construction above then you need to tick here

If you answered TICKED ALL of the questions above it is likely that either internal dry-lining or external insulation would be appropriate for your home.

Option I – Internal Dry Lining of Walls

The standard method for insulating internally is to fix insulated dry-lining panels (consist of plasterboard with insulation bonded to it and with an integral vapor barrier) to the walls. The main considerations are:

  • -Lower cost to implement than external insulation
  • -Disruption due to installation works and small loss of room space due to the insulation
  • -Possible reinstallation of services (such as electrical wiring, sockets and heating radiators)
  • -Redecoration required after the installation works.

Option II – External Insulation of Walls

Installing external insulation involves fixing insulation materials to the outer surfaces of walls so that the house is effectively ‘wrapped’ in insulation. Typical insulation materials used are mineral fiber slabs, expanded polystyrene, extruded polystyrene, polyurethane and Phenolic foam. The insulation is covered with a render known as a basecoat, a reinforcing mesh providing strength and resistance to damage from impact, and a render finish. The main considerations are:

  • -Higher cost to implement than internal dry-lining
  • -Aesthetic acceptability of the finish proposed
  • -Planning permission may be required
  • -Window sills and eaves may need to be extended, downpipes and cables will need to be relocated
  • -Special consideration should be given to adjacent properties when living in a terraced or semi- detached home
  • -If your property is an apartment it may not be possible to do external insulation in isolation

Note: External wall insulation is not suitable for timber frame type construction.


3a. Heating Controls .

- Do you currently have a central heating system that heats hot water which is then circulated around your home via radiators or other heat distribution .

- Do you lack good heating controls on your heating system?

Hint: Good heating controls allow for separate heating of the hot water from the room heating and have different time and temperature settings for different days of the week?

If you answered TICKED ALL of the questions above it is likely that improved heating controls would be appropriate for your home.

Adequate heating controls can help a homeowner to accurately match your space heating and hot water schedules to the working and living patterns at the house. As a minimum, your heating systems should be split into two independently controlled zones namely your 'Space Heating Zone' and your 'Domestic Hot Water Zone'. Additional zones can also be put in place in large homes to split upstairs and downstairs or living areas and bedrooms.

-Splitting your heating into zones may require rerouting of existing pipe-work involving some disruption to the home

-The installation of controls will also as a minimum require your existing system to be fully drained by your plumber

-Caution with older solid fuel heating systems which will likely have no valves or controls on the primary circuit


3b. Heating Controls with High Efficiency Boiler

- You currently don’t have a central heating system i.e. you currently only have free-standing electric, gas or solid fuel heaters or fires to heat your home or is your current boiler older than five years?

HINT: Most boilers installed after 2007 would be condensing boilers – consult with your plumber to verify if you don’t know.

If you answered TICKED EITHER of the questions above it is likely that a high efficiency gas or oil boiler coupled with improved heating controls would be appropriate for your home.

Older conventional boilers can be wasteful of energy as a significant portion of the heat is lost up the flue/chimney. The latest models of high efficiency boilers capture more of this heat

-The installation of a new central heating system in an existing home can be relatively disruptive in terms of pipe routing

-Replacing an existing boiler may be less disruptive though this depends on the type and location of the existing boiler


  • Home Energy Saving scheme
  • The Sustainable Energy Authority of Ireland
  • P.O. Box 119, Cahirciveen, Co. Kerry
  • Phone: 1850 927 000
  • Web: www.seai.ie/hes
  • E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

The Sustainable Energy Authority of Ireland is financed by Ireland’s EU Structural Funds Programme co-funded by the Irish Government and the European Union