Skip to main content
HELPERG Ecosystem
Build Design HubBuild Design Hub

Building components

Envelope Layers & Barriers

Continuous positioned layers within a build-up — insulation, separation, protection, drainage and root barriers — named by the job they do rather than the product used.

6 entries in this category.

Overview

About this category

Several elements in a build-up are not discrete objects but continuous planes: a layer of insulation, a sheet separating two incompatible materials, a board protecting waterproofing from what is laid over it. Naming the position separately from the product matters because the same position is filled by very different materials in different assemblies.

This category is deliberately short. Where a control layer already exists as a published material or building system — the vapour control layer, the breather membrane, the air barrier, the water control layer — no component duplicates it, and these entries point at those instead.

Boundaries

What this category covers, and what it does not

  • Covers continuous positioned layers that are defined by function within a build-up.
  • Does not cover the membranes, boards, insulants and geotextiles that fill those positions, which are published material entries.
  • Does not duplicate the air barrier, vapour diffusion control or water control layer, each of which is a published building system.
  • States no thickness, resistance, permeability, U-value or performance figure of any kind.

Browse

Forms and roles in this category

Descriptive labels for what is here. They are a way of reading the list, not a filter and not a ranking.

Forms:Continuous layerVoid or cavity
Roles:DrainageInsulationMoisture controlProtectionSeparation

Entries

Layers & Barriers components

Every entry in this category. Each explains what the element is, what it depends on, and how it relates to materials, systems and junctions.

Continuous layerDrainage Layer →A layer that lets water move freely within a build-up to a point where it can be collected and removed.Continuous layerInsulation Layer →The positioned thermal layer within a build-up, defined by where it sits and what it must stay continuous with.Continuous layerProtection Layer →A layer placed over a vulnerable element so that subsequent work and later loading do not damage it.Continuous layerRoot Barrier →A layer that stops plant roots reaching and penetrating construction they would otherwise grow into.Continuous layerSeparation Layer →A layer placed between two materials to keep them chemically or physically apart, or to let them move independently.Void or cavityVentilated Drained Cavity →The space behind a cladding or covering that lets water drain away and lets air move so what is behind it can dry.

Related reference libraries

Components are what materials become and what systems are made of. The three libraries answer different questions and are kept deliberately separate.

Materials Library →Building Systems →