Archives: Glossary

  • Pressure Relief Valve

    A safety valve that releases pressure if a heating or hot water system becomes over-pressurised.

  • Planning Permission

    Formal consent that may be needed for some external changes, such as external wall insulation, solar panels in sensitive areas or alterations to listed buildings.

  • PIR Insulation

    Polyisocyanurate insulation board. A rigid foam board commonly used in walls, floors and roofs.

  • Photovoltaics

    Solar panels that generate electricity from daylight.

  • Phenolic Insulation

    A rigid insulation board with good thermal performance for its thickness.

  • Perimeter Insulation

    Insulation installed around floor edges or foundations to reduce heat loss at junctions.

  • Penetrating Damp

    Moisture entering through the building fabric, often due to defects such as failed pointing, cracked render, roof leaks or blocked gutters.

  • Peak Load

    The highest heating demand expected during very cold conditions.

  • Party Wall

    A wall shared between two properties. It may need consideration during insulation, airtightness or ventilation works.

  • Party Wall

    A wall shared between two properties. It may need consideration during insulation, airtightness or ventilation works.