Energy renovation across several buildings: setting priorities and comparing results
PIR insulation
A thermal modernisation programme covering several buildings needs a common assessment method and separate solutions for each property. A school, a residential building and a commercial unit differ in operating hours, the condition of the building envelope and how the services perform. On Izoprofil.eu we describe how to prepare the order of renovations: gathering data, identifying urgent defects, selecting the scope and checking the results once the works are complete. PIR boards can be one of the insulation materials, especially where the geometry of the existing detail limits the space available for layers. Their suitability, however, is determined by the requirements of the specific building element. A shared schedule of the investment helps compare the needs of the buildings without attributing the same savings to all of them. The reference point should be energy consumption together with a description of comfort and how the building is used.
In this article
Create a data sheet for each property
The building record should indicate its function and actual pattern of use.
Gather information on heated areas, building components, the heat source and ventilation. Add consumption readings with dates and users’ comments on overheating, cold or moisture. Mark data from an incomplete period as incomplete. A missing measurement is not zero consumption and should not improve the building’s position in the comparison.
Separate urgent repairs from energy improvements
A leaking roof, damaged flashings or a damp substrate require investigation regardless of the planned insulation. In the schedule, separate the work removing the cause of the damage from the work improving thermal performance. Covering an unidentified defect with a new layer makes later diagnosis more difficult and may force repeated dismantling.
The order of investment should not be decided solely by the highest bill. Technical condition, the possibility of temporarily closing rooms and the scope of work shared with other renovations also matter. The criteria should be named before comparing buildings. This way, an urgent repair of a school and the modernisation of heating in a flat remain different tasks, even when they are financed from one plan.
Establish the dependencies between the works
Set out which works affect the next ones. Insulating building components changes the heat demand, replacing windows may require adjusting ventilation, and rebuilding the roof affects flashing heights and drainage. Designers of the individual trades should work to an agreed target state, also when execution is spread over time.
Assess the PIR variant at the place where it is used. The available height at the threshold or parapet may be a constraint, but requirements for load-bearing capacity, moisture, fire protection and compatibility with adjacent layers remain. The choice of insulation core does not automatically determine the facing, the bonding method or the permissible load on the finished component.
Compare variants on the same assumptions
For each variant, define the same scope of costs. Replacing only the insulation and a renovation covering the substrate, waterproofing and drainage are not equivalent offers. Record preparatory work, temporary protection and restoration of equipment. Mark separately the items whose cost remains undetermined until the existing layers are exposed.
The assumptions behind energy calculations should be explicit. Temperatures, usage patterns and the assumed condition of the installations are stated. If the compared variants rest on different assumptions, the difference in result does not describe the material alone. Likewise, a shorter heating period after renovation may change consumption regardless of the quality of the insulation.
Plan the handover of the building for operation
Before the works are completed, prepare the person operating the building for the new equipment settings and the required inspections. The instructions should cover the products used and the actual layout of the installations. The as-built documentation must reflect the approved changes, not only the original version of the design.
Handover of the facility also covers the roof and elements not accessible from the rooms. Establish how drains, service penetrations and repair locations are to be checked. In a building used by several parties, designate responsibility for reports. A leak revealed after rain should reach the person able to link it to the scope of works carried out.
Check results under comparable conditions
Compare energy consumption taking into account the weather, the number of users and the operating hours. The invoice amount also depends on prices and the billing method. Presenting energy and costs separately avoids confusing the effect of the renovation with a change of tariff. Give the result for a specific period and building.
Evaluation of the programme should take account of comfort and ease of operation, not only the total of the bills. Recorded comments may indicate the need to adjust the installations or repair a detail. Conclusions from the first project help prepare the next, but do not justify copying its design without checking the new building.
7 branches. Materials closer to your project.
