Sustainability in Older Buildings. Glenribbeen — The Eco-Blog

Sustainability in Older Buildings. Glenribbeen - The Eco-Blog

Improving the Insulation on Older/Poorly-Built Buildings.

AKA Raising the B.E.R. on (older) buildings.

The B.E.R. Rating. Building Energy Regulations of a building means to improve it’s insulation and ultimately to lower its eco-footprint and cost in terms of fuel-consumption. It’s a frightening thought that buildings bought before the UK building boom of the ‘80’s (Ireland of the late 90’s) now cost more to heat per year than the initial cost of the building itself. Fuel prices have risen at 1.5 times the rate of inflation over the last 30 years.

It is generally accepted (B.E.R. standards, LEED (US), SAEI- Ireland, Department of Energy and Climate Change (DECC); UK) that 35% of heat is lost from a building via poorly insulated walls.

Heat is lost in ALL directions.

The overall heat loss from a building can be calculated as

H = Ht + Hv + Hi   where H = overall heat loss (W)

Ht = heat loss due to transmission through walls, windows, doors, floors and more (W)

Hv = heat loss caused by ventilation (W)

Hi = heat loss caused by infiltration (W) .

Heat-loss in buildings (or heat0gain in warm lands demands the value of the building every generation or less nowadays. (Protek-usa. Heat-Gain-Loss-Buildings.pdf). this pdf starts with a very good definition of heat loss via radiation, conduction and convection.

N.B. Sand-cement render on the exterior of a building (especially if insulating the interior) will result in the building ‘sweating’ and possibly developing Merulius lacrimans – dry rot – or -Serpula lacrimans ‘Real-Dry-Rot’). Both will destroy a building and even its neighbours. If a house is to be ‘sealed’ great care must be taken that it remains “breathable ”.

There are two (generally) accepted ways of insulating a building (insulating the envelope);

External; “Bubble-wrapping” the exterior – e.g. polystyrene slabs fixed to the exterior walls (using plastic ‘mushroom’ plugs) and plastering with a patent-polybond-skim over a mesh that holds all in place. This technique ‘defaces’ the exteriors and ‘technically’ needs planning permission.

Cross-section of external insulation.

Internal; fitting patent pre-insulated slabbing to interior walls (ceilings too if possible) to retain the heat generated within the building. Fixed as above or with laths between wall and slab this system is usually seen as the best as it retains heat before it hits the exterior wall and is absorbed (before being lost if there’s no external insulation). This system is often eschewed as it reduces the volume of the room (room-size) considerably in small homes/offices. It is seen as the most desirous in larger buildings as the heat is retained and in fact rather like any light-weight structure (boat-caravan) is easily heated very quickly.

In both cases however the incidence of leakage (drafts) and of course doors, window, and especially glazing must be considered. Poor glazing techniques (ie single-glazing or poorly designed/compromised/faulty) can cost 23% heat loss normally but even far more if the rest of the structure is well insulated.

Sustainability in Older Buildings. Glenribbeen - The Eco-Blog

From seai.ie/(Power_of_One) ; “Internal insulation systems involve using insulated dry-lining boards. These boards comprise of 12.5mm of plasterboard with insulation bonded to the back with a vapour barrier between the two. The insulation ranges in thickness from about 25mm to approximately 60mm though this depends on the make and availability. A lot of these boards would have similar levels of thermal conductivity because the main types of materials that are used, i.e. polyurethane and polyisocyanurate, have very similar thermal properties. However, it has the disadvantage of placing the thermal mass of the wall outside your heating envelope. External insulation is another option, which would have the added advantage of keeping the thermal mass of the concrete walls within your envelope. It is very popular method in Europe, and is becoming more common in Ireland. With external insulation, the insulation panels are applied to the walls, then a protective mesh that protects the insulation against impact damage is applied, then a basecoat and usually two coats of render”.

Floors are often disregarded as it’s generally thought that heat rises – which is true. But as temperature rises within a structure the heat will always seek to find a way out; even downwards. Floor insulation must reflect what is planned above. 15% heat loss is the accepted figure but again as the better insulation of the upper areas improves the rate of loss through the floor will increase.

Air Seal

A gap of just 1/8 of an inch under a 36-inch door lets in as much air as having a 2.4 inch wide hole in the wall. Since people often adjust the thermostat and leave heat running longer when they feel a draft, preventing air infiltration can greatly reduce energy usage. See Notes below.

Air-pressure-tests and infra-red video cameras

will show leaks and vents as well as cool-spots in covered areas that are lacking insulation.

Detailed business information on Air Pressure Testing Companies located in the UK, including photos, contact details and customer reviews. freeindex.co.uk/air_pressure_testing/

Heat-Exchange Systems. aka Heat Recovery System.

No discussion on heating/cooling any building can Not but consider heat-exchange-system see; Heat-Exchange Systems.


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