How should insulation, ventilation and air-conditioning be planned together?

Start with the problem you want to solve. A room that overheats, a bedroom affected by noise and a bathroom with condensation may need different investigations. Replacing a machine or adding insulation without understanding the cause can leave the original problem unresolved.

Record how the home behaves

Note when the discomfort occurs, which rooms are affected, how windows and shutters are used, and whether damp marks change with weather or occupancy. Give the designer access to any existing energy assessment, installation records and maintenance information.

These observations help define the investigation; they are not a diagnosis. Damp can have different causes, and treatment should follow an assessment of the source. Avoid choosing a wall lining or impermeable finish simply to cover a visible symptom.

Compare improvements to the envelope

Ask the designer to compare relevant options: repairing existing joinery, improving glazing where permitted, shading, roof or wall insulation, and treatment of junctions. The suitable approach depends on construction, moisture behaviour, available space and the extent of the works. The Código Técnico de la Edificación applies to existing-building interventions within its scope, with compliance justified in the project or technical report. Where full application is not feasible for specified technical, economic, planning or heritage reasons, the competent designer must justify the achievable solution and its limitations.^[1]

Changing windows or external elements can affect the building’s appearance and common property. Protection may also limit materials or details. The municipal ordinance provides a heritage viability consultation and specific documentation for protected properties and archaeological areas. Check the building’s catalogue entry, protected surroundings and the proposed intervention before choosing a permission route or altering original elements.^[4] Confirm those constraints before ordering a product described as a universal upgrade.

Include ventilation in the same design

Consider where air enters, how it moves through occupied rooms and how wet rooms and cooking areas are ventilated. A proposal that changes the envelope or layout should assess the ventilation strategy at the same time. The applicable CTE requirements depend on the intervention and must be identified by the responsible technician. ^[1]

Space for ducts, grilles and maintenance access should appear on the drawings. A visually discreet installation is only useful if it can be inspected, cleaned and maintained. In a flat, shared shafts and façade openings require particular attention to ownership and permissions.

Size and locate heating or cooling equipment

The competent installer or designer should assess the load and choose an appropriate system, rather than selecting only from the size of the floor area. RITE covers fixed heating, cooling, ventilation and domestic hot-water installations, including the reformed part of an existing installation. The scope and capacity determine the technical documentation and commissioning requirements; applicable certificates and operating information form part of handover.^[2] Compare the scope of the equipment, distribution, controls, condensate disposal and maintenance access.

Outdoor units need an agreed location. Discuss façade appearance, neighbours, vibration and the route for pipes and condensate before a position is fixed. An owner must notify the community’s representative before works inside a flat. Article 7.1 allows those alterations only if they do not impair the building’s safety, general structure or exterior configuration, or prejudice another owner’s rights; notice alone does not authorise changes to common elements.^[5] Where common elements are changed, the community decision and applicable requirements must also be addressed. ^[5]

Coordinate electrical capacity and controls

REBT requires low-voltage installation work within its scope to be carried out by authorised installation businesses, with the project or technical report, verification and certification appropriate to the work. The owner receives use and maintenance information; an inspection by a control body is required only for the specified cases.^[3] The electrical installer should assess the proposed equipment alongside the rest of the home’s installation. Record any work to circuits or controls in the specification, with the applicable testing and documentation.

Ask for controls you can use and understand. For owners who are away frequently, remote control may be convenient, but it should be discussed with the equipment supplier, including connectivity, account access and what happens if the connection fails.

Compare evidence, not savings promises

A proposal should identify the assumptions behind any calculated performance. We do not promise a universal percentage saving or a specific energy rating for an unassessed home. Ask the technician to explain the expected benefit, the limitations of the assessment and what will be checked at completion.

At handover, obtain the relevant installation documents, operating instructions and maintenance requirements. Have the controls demonstrated and keep the service access points identifiable. These checks belong in the overall renovation handover, alongside the visible finishes.