A Guide to Solid Wall Insulation

Agenda

• Introduction

• Solutions

• Internal Solutions

• External Solutions

• Summary

• Questions

Introduction – The facts about Hard to Treat Homes

• HTT homes account for 43% of stock but actually emits over half the CO2 from all homes.

• Over half of the HTT stock is in the private sector.

• 65% of PRS is HTT

Introduction – The facts about Hard to Treat Homes

• HTT properties tend to be more difficult and expensive to improve in terms of providing adequate insulation and heating.

• Over 50% of fuel poor households live in HTT homes

• There are around 9.2 million dwellings that can be considered HTT (43% of the housing stock)

• 6.6 million properties have solid walls (31% of the total housing stock)

• Of the 326,000 high rise flats in England 48% have solid walls.

Introduction - What is a Hard to Treat Home?

These types of property often fall into one or more of the following categories:

• Solid wall construction

• No loft space

• Off the mains gas network

• Non traditional construction

• Non standard cavity

Introduction - What is a solid wall?

• 9” masonry walls and other non-traditional construction types such as single leaf masonry, >9” walls (e.g. thick stone walls)

• concrete walls, metal or timber panels and some mixed wall types (e.g. Where the ground and first floors are constructed of different materials)

• BRE estimate that around 7% of unfilled cavity wall stock cannot receive CWI.

• High rise flats (at least 6 storeys high) – esp. 1953-1972

• Hard to treat not really…. expensive to treat as opposed to loft and cavity

• Solid wall solutions

• Internal and external

Introduction - What is a solid wall?

External Render SystemInternal Flexible LiningInternal Dry Lining (Direct Fix)Internal Dry Lining (On Straps)Internal Dry Lining (Filled Studs)

Internal Wall Solutions

Rigid boards

What are the solutions?

Typically consists of either dry lining in the form of flexible thermal

linings available in 1 metre by 12.5 metre rolls, laminated insulating

plasterboard (known as thermal board), or built-up systems using

fibrous insulation such as mineral wool held in place using a

studwork frame.

Internal Wall Solutions

Flexible thermal lining Rigid board

Case Study – Flexible thermal lining

SEMPATAP

The problemA solid wall Victorian terraced property with an uninsulated converted loft space.

The solutionSempatap is thermal insulation on roll which is applied like wallpaper and at only 10mm thick does not cause significant disruption during installation.

This product can be applied to ceilings as well as walls and provides a solution for properties without a loft space as well as those with solid walls. It can also be applied to the underside of floorboards in a cellar/basement.

Internal Wall Solutions

Case Study – Flexible thermal lining

Internal Wall Solutions

Case Study – Flexible thermal lining

The product is applied using a special adhesive using a roller or brush and can be easily cut to size using wallpaper shears or scissors.

Once the product has been applied it can be painted, papered or even tiled.

The manufacturer of this product expect it to have a life expectancy of 30 years.

Due to the flexibility of the product it can be used on uneven walls and irregular surfaces and can be used on sloping walls and ceilings in converted loft spaces.

The product is only applied to the exterior facing interior walls of the property.

Internal Wall Solutions

Training and time frames(Flexible thermal lining)

SEMPATAP TRAINING

– On site training is provided for all contractors in the application of Sempatap Thermal

– On site training is always preferred as it covers a real life installation and the difficulties that can be encountered

– The trainer acts as part of the installation team for the period of training

– Training is carried out on site and frequently takes place in occupied properties.

SKILLS– Sempatap Thermal is not difficult to apply, the skills required

are similar to a decorator/wallpaper hanger or dry lining contractor

Internal Wall Solutions

Case Study – Rigid boards

SPACETHERM

The problemContinuity of the existing cavity fill missing in places and dampness.

• Damaged external render led to damp inner wall surfaces • Internal damp led in turn to cold spots and mould growth• Cold bridging at door/window lintels

The solutionAerogel insulation was laminated to Fermacell. The existing lath & plaster was removed and the thermal laminate fixed directly through the board to the existing brick.

Internal Wall Solutions

Case Study – Rigid boards

Internal Wall Solutions

Case Study – Rigid boards

The solution

• No specialist contractors required

• Can be installed room-by-room with tenants in situ

• Does not require upgrading entire blocks at once

• Increases internal surface temperature

• Improves response to heating input when heated intermittently

• Lowest thermal conductivity available (0.013 W / mK)

• Hydrophobic, allowing installation on damp substrate without drying periods

• Integrated foil layer, reducing condensation risk on solid walls

• Fermacell wallboard allows fixing of units, radiators, etc to inner surface, reducing cold bridging

Internal Wall Solutions

Case Study – Rigid boards

Internal Wall Solutions

Training and time frames (Rigid boards)

• No specialist skills required- tradesman level

• Training can be given on first installation with some systems

• Final surface may need plaster/tape and filling depending on client preference

• Depending on the system, will be screwed or dot and dab

• Installation time of an average 3 bedroom semi is 2.5 days for 2 man team after preparation work

• Price depends on system and thickness but is around £10- £55/m2

• Ancillary costs of skirting boards, sockets etc.

SPACETHERM

Internal Wall Solutions

Site supervision and surveys

• A survey of the property is required to assess the suitability of the substrate and assess any ancillary work required

• Supervision will vary depending on the system

• Low level of supervision required with most systems

Internal Wall Solutions

What are the solutions?

Comprise of an insulation layer fixed to the existing wall, with a protective render or decorative finish. Dry cladding offers a wide range of finishes such as – timber panels, stone or clay tiles, brick slips or aluminium panels.

External Wall Solutions

Why Externally Insulate?

• To meet the Decent Homes Standard

- A decent home is windproof, weathertight and warm, with modern facilities

- The Government expects all homes to meet this standard by 2010

• Increases thermal quality of the building- Particularly relevant when refurbishing non-traditional housing

• Overcomes moisture/condensation issues

• Protects the existing building envelope

• Reduces heating bills by 25%

• Improves the building’s appearance

External Wall Solutions

What is External Wall Insulation?

• A method of upgrading the thermal performance and external appearance of existing properties

• Insulated and rendered properties are transformed into warm, energy efficient and attractive homes/buildings

Before After

External Wall Solutions

External Wall Insulation – Key Components

External Wall Solutions

• Beads and closures

• Insulation

• Fixings

• Reinforcement layer

• Base render coat

• Finish coat

Insulation Properties:

EPSMineralWool

Phenolic Cork PIR

Thermal Conductivity w/m2k

0.037 0.036 0.020 0.038 0.028

Fire Performance

Emissions Production

Recyclability x x x

Impact Resistance

Cost

Key: = Excellent, = Good, = Adequate, X = Poor

Choice of Insulation – Comparative Performance

External Wall Solutions

External Wall Solutions

• Hand applied base coat • Hand applied finish coat

• Brick slips• Machine applied one coat

Rendering options

Finishes available

External Wall Solutions

Mineral render scraped texture

Dry dashusing 6-8mm

coloured aggregate

Spray roughcast

Brick slips or brick-effect render

Light synthetic aggregate

using an acrylic binder

Upgrading Housing Stock

– Myton

– Swedish Timber

– Tarran

– BISF

– Reema

– Wimpey No-fines

– Unity

– Easiform

– Spooner

– Airey

– Solid Brickwork

– Traditional Masonry Cavity

• Common Property Types

External Wall Solutions

Benefits of External Wall Insulation for Solid Walls

External Wall Solutions

• No internal living space is lost

• Minimum disruption involved – decanting of residents not required

•Condensation risk moved to outside of system – structure stays warm and dry

•Low u-values achieved saving carbon emissions and energy costs

• Minimal maintenance once installed

•Equally suitable for low and high rise schemes with funding available