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Insulation

22 articles

Airtightness & Air Pressure Testing: Where Leaks Happen & How to Seal Them

Airtightness and blower door testing: air permeability targets, common leakage paths, membrane installation, smoke testing
Breathable Membranes for Roofs and Walls: When to Use Them and Which Grade
Cavity Wall Insulation Types: Mineral Wool vs EPS Bead vs Phenolic Board — Selection Guide and Part L Requirements

Mineral wool vs EPS bead vs phenolic full-fill board; λ values; exposure-zone suitability (driven rain); retrofit injection vs new-build batts; Part L target U-values; PAS 2035; complements u-value-calculator
Cavity Wall Insulation: Blown Fibre, Foam & Bead — When It Goes Wrong

Cavity wall insulation: blown fibre, EPS bead, PUR foam; when cavities are unsuitable, remediation for failed installations
EPC Ratings Explained: What They Mean, How They're Calculated & Improvement Measures

EPC ratings A–G explained: SAP calculation method, band thresholds, improvement measures, minimum E for landlords (MEES)
Floor Insulation: Suspended Timber, Solid Concrete & UFH Compatibility

Floor insulation: suspended timber (100mm mineral wool), solid concrete (PIR boards), compatibility with wet UFH systems
How Is External Wall Insulation (EWI) Installed and What Are the Building Regulations?

EPS/mineral wool/phenolic EWI: U-value targets (0.30 W/m²K existing), PAS 2030/2035 for funded work, fire performance over 18m, SWIGA/CIGA guarantees, detailing at openings
Interstitial Condensation: What It Is, Why It Matters and How to Prevent It
Loft Insulation Types: Mineral Wool vs Blown Cellulose vs Spray Foam — Depths, R-Values and Grant Eligibility

Mineral wool 270-300mm to 0.16 W/m²K; blown cellulose; spray foam (open/closed cell) and mortgage-lending caveat; cold vs warm loft; ventilation to avoid condensation; ECO4/GBIS grants; PAS 2035
Loft Insulation: Materials, Depths, Ventilation & Building Regs Part L

Loft insulation: 270mm mineral wool target, cold roof ventilation (1:150 ventilation ratio), Approved Document L requirements
MVHR Installation: Mechanical Ventilation with Heat Recovery — Ducting, Commissioning and Part F

MVHR installation: Part F 2021 System 4, ≥85% heat recovery new build, ducting sizing and routing, balanced commissioning ±10%, F7/G4 filter classes, summer bypass, SFP ≤0.8 W/(L/s); SAP Appendix Q certification
Secondary Glazing: Retrofit Options, U-Value Improvement, Permitted Development Rules and Listed Buildings

Internal pane, original window kept; ~1.7-2.0 U-value, up to ~45-50dB acoustic (wider gap = better); thermal gap ~20mm, acoustic 100-200mm; PD but listed building consent may still apply; Historic England favours it
Solid Wall Insulation: Internal vs External — Costs, Disruption & Condensation Risk

Solid wall insulation: IWI vs EWI; vapour control layers, cold bridging at reveals, planning considerations for EWI
Thermal Bridging: What It Is, Where It Happens & How to Fix It

Thermal bridging: linear and point bridges, psi values, party wall junction, window reveal details, Approved Document L
Vapour Control Layers: Sd Values, Correct Positioning in Roof and Wall Build-ups, BS EN ISO 13788

Sd values (barrier ≥100m, VCL 2-100m, breathable ≤0.3m); warm-side-tight/cold-side-open ~5:1; no double barrier; BS 5250 / BS EN ISO 13788 Glaser; intelligent VCLs for retrofit; sealed laps/AVCL
Ventilation Strategy: Natural, MEV, dMEV & MVHR — Part F Requirements

Ventilation strategies: natural, dMEV, MEV, and MVHR — Part F 2021 flow rates, commissioning requirements
What Are the Options and Risks of Internal Wall Insulation?

IWI types (PIR, stud frame, cork, woodfibre), condensation risk at joist ends, VCL requirements, planning implications, PAS 2035 High Risk classification
What Are the Risks of Spray Foam Insulation in Roofs?

Mortgage lending problems (RICS/UK Finance guidance), removal costs (£1,500–£4,500), vapour permeability loss, closed-cell vs open-cell differences, Ofgem ECO scheme complaints
What Is the Difference Between Warm Roof and Cold Roof Construction and Which Should I Specify?

Cold roof (insulation at ceiling, 50mm ventilated void) vs warm roof (insulation above deck), BS 6229, 1:150 ventilation ratio, condensation risk, Part L compliance
What Natural Insulation Materials Are Available and When Should They Be Used?

Sheepswool, hemp fibre, wood fibre, cellulose, cork compared: lambda values, vapour-open vs vapour-closed, fire performance, breathable construction compatibility
What Thickness of Pipe Insulation Is Required for Compliance?

Part L1B pipe insulation tables, BS 5422:2009, frost protection in unheated spaces, vapour barrier on chilled pipes, material types (mineral wool, foam, phenolic)
Which Rigid Insulation Board Should I Use? PIR vs EPS vs XPS vs Phenolic

PIR (~0.022), EPS (~0.032), XPS (~0.034), phenolic (~0.020 W/m·K) compared: compressive strength, moisture resistance, fire performance, applications and BBA certificates