Insulated Ground Floors - forterra-jetfloor.co.uk

Hanson Building Products

Insulated Ground Floors

NEW & IMPROVED DESIGN

Insulated
Ground
Floors

Jetfloor from Hanson
has been the market
leading solution for
thermally insulated
structural ground
floors since its
introduction in 1982

And now it’s
even better.

Jetfloor was the UK’s first system to use System Overview
expanded polystyrene blocks combined
with a structural concrete topping to Our new Jetfloor consists of The unique Thermalite Psi-
provide high levels of thermal insulation. standard 150mm and 225mm Block® reduces thermal linear
Over decades it has been successfully prestressed concrete beams bridging and improves the Psi
used in tens of thousands of new homes. positioned at varying centres value at floor and wall junctions
Today our latest development of Jetfloor dependent on load conditions. helping reduce the overall
presents the platform for a range of ‘U’ dwelling emission rate (DER).
values and enhanced Psi values providing The beams are infilled with
a future-proofed robust solution for expanded polystyrene (eps) blocks The floor is completed with
housebuilders, specifiers and homeowners. which are supplied in lightweight a structural concrete topping
easy to handle lengths enabling reinforced with polypropylene
2 | Hanson Jetfloor rapid coverage of large areas fibres laid over a minimum of
of floor. 80mm eps sheet insulation.

The eps blocks are available in a Hanson Concrete specification:
range of configurations providing
a flexible approach to achieving •• 7 0mm concrete strength
‘U’ values. class RC25/30

•• Reinforced with polypropylene
fibres or steel mesh reinforcement

8 6

3 7
2 9

4

1

5

Jetfloor Benefits Jetfloor components
1. 150mm or 225mm
Thermal Sustainability
„„Flexible ‘U’ value performance prestressed beam
„„Improved Psi value due „„A+ Green Guide rating 2. Thermalite spacer block
„„Reduced dwelling 3. Eps infill block
to unique Psi- Block® 4. Psi-Block®
„„Thermal mass emission rates 5. Damp-proof course
„„Accredited to BS EN 6. 140mm Thermalite coursing
Cost of construction
„„Reduced excavation 14001 and BES 6001 block for screed rail
responsible sourcing 7. 80mm eps 125
and spoil removal
„„No waste Quality overlay sheet
„„Increased speed of build 8. 70mm concrete topping
„„No specialist skills required „„M anufactured in a quality 9. Membrane if required
controlled environment in
accordance with BS EN Service
ISO 9001:2000 „„Available nationwide
„„Supply only or supply
„„CE marked and certified by
the BBA to latest relevant and install
codes and standards „„Comprehensive

in-house technical
support

Hanson Jetfloor | 3

Thermal Performance

‘U’ values W/m² K ‘U’ value W/m² K

The measure of heat-loss ‘U’ values may be required. P/A 0.038 λ 0.030 λ
through the fabric of a building The new improved Jetfloor
is expressed as a ‘U’ value with provides a range of ‘U’ 0.3 0.160 0.137
limiting values set out in the value options that will help
building regulations. However, improve the overall DER. 0.4 0.168 0.144
to fully comply with the building
regulations, the overall dwelling The following table 0.5 0.174 0.148
emission rate (DER) must be demonstrates this range
lower than the target emission based on specific Perimeter/ 0.6 0.178 0.151
rate (TER) when calculated Area Ratios and insulation
in SAP. To achieve this, lower material lambda values (λ). 0.7 0.182 0.153

0.8 0.184 0.155

Note: ‘U’ values are based on NJB1
beam centres. Actual house-type values
will vary dependent on floor layout.

‘λ’ values (W/m K) and ‘Y’ values (W/m² K)

Heat is also lost through thermal the building being considered The new Jetfloor incorporating
the new ‘Psi-Block®’ has resulted
bridges or junctions in a building i.e. the wall to floor junction. in significantly improved Psi values
as shown on the following table:
and is expressed as a ‘Y’ value. Its The Psi value is the measure of

units of measure are the same as the thermal transmittance at the

the ‘U’ value W/m² K. To calculate thermal bridge and is calculated Psi value
(W/m² K)
the ‘Y’ value the length of the using thermal modelling, its Floor Detail

thermal bridge must be multiplied units of measure are W/m K.

by the Psi value of the junction of New Jetfloor 0.03 to 0.10 (1)

Accredited 0.16 (2)
construction details 0.32 (2)
SAP conventions
document default

(1) V alues based on wall U-value of 0.28 W/m2 K
and floor U-value of 0.15 W/m2 K.

(2) From SAP table K1.

4 | Hanson Jetfloor

Hanson Jetfloor | 5

Structural Performance – Load-span tables

Prestressed beams Beam details

77 Beam Width Height Weight Weight
225 Reference (mm) (mm) (kN/m) (kg/m)
33.24
73 165 135 BT02 125 150 0.326 63.40
150 150
RD09 215 150 0.622 58.74
125 215
T008 135 225 0.576

The load-span tables below are given as a
guide only. Further advice is available on request.

Load-span tables

(Based on floor finishes of 70mm thick concrete topping having minimum strength class RC25/30 reinforced with
either polypropylene fibres or steel reinforcement mesh on sheet material of minimum compressive strength 125N/mm2)

Ref Self Weight Imposed load kN/m² 225mm Beam 225mm Beam 225mm Beam 150mm Beam 150mm Beam 150mm Beam 150mm Beam 150mm Beam 150mm Beam 125 485 125 485 125
NJB1 kN/m² 1.50 2.00 2.50 3.00
0.56 Maximum Clear Span (m)
4.45 4.20 3.95 3.75

Ref Self Weight Imposed load kN/m² 125 295 125 485 125
NJB2 kN/m² 1.50 2.00 2.50 3.00
0.66 Maximum Clear Span (m)
4.80 4.50 4.25 4.05

Ref Self Weight Imposed load kN/m² 125 295 125 295 125 295 125
NJB3 kN/m² 1.50 2.00 2.50 3.00
0.8 Maximum Clear Span (m)
5.20 4.90 4.65 4.40

Ref Self Weight Imposed load kN/m² 215 485 215
NJR1 kN/m² 1.50 2.00 2.50 3.00
0.92 Maximum Clear Span (m)
5.75 5.45 5.15 4.90

Ref Self Weight Imposed load kN/m² 215 485 215 295 215
NJR2 kN/m² 1.50 2.00 2.50 3.00
1.06 Maximum Clear Span (m)
6.10 5.75 5.45 5.20

Ref Self Weight Imposed load kN/m² 215 295 215 295 215
NJR3 kN/m² 1.50 2.00 2.50 3.00
1.25 Maximum Clear Span (m)
6.50 6.15 5.85 5.60

Ref Self Weight Imposed load kN/m² 135 485 135 485 135
NJT1 kN/m² 1.50 2.00 2.50 3.00
0.96 Maximum Clear Span (m)
6.90 6.50 6.20 5.90

Ref Self Weight Imposed load kN/m² 135 485 135 295 135
NJT2 kN/m² 1.50 2.00 2.50 3.00
1.14 Maximum Clear Span (m)
7.35 6.95 6.65 6.35

Ref Self Weight Imposed load kN/m² 135 295 135 295 135
NJT3 kN/m² 1.50 2.00 2.50 3.00
1.38 Maximum Clear Span (m)
7.80 7.55 7.20 6.85

6 | Hanson Jetfloor

Section Details

Detail 5

Detail 1

Typical layout Detail 4

Less than 300mm

LESS THAN 300MM

Detail 2 Detail 6
Detail 3
Detail 7

Hanson Jetfloor | 7

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456
789
10 11 12

Installation Guide

This installation guide provides step-by-step instructions required to install
the new Jetfloor system. The installation team shall refer to the beam
setting out drawing which has been approved and issued prior to delivery.

Step-by-step instructions

1 Lay DPC on top of the bearing 6 Once the beams have been 9 If required install the
wall. This wall must be constructed positioned the polystyrene infill perimeter edge insulation strips
in advance of the floor being blocks can be inserted. The blocks against the perimeter wall.
installed to allow the mortar can be cut with a hand saw and
to reach its design strength. off cuts from the end of a run can 10 Install any gas carcassing
be reused within the floor. Any or underfloor heating pipes that
2 Using suitable plant equipment holes required for service pipes may be required. This can be
place the prestressed concrete can be cut out of the blocks. secured to the top insulation sheet
beams at the approximate material using standard pipe clips.
locations and centres as shown 7 Bed the Thermalite coursing
on the approved drawing. blocks around the perimeter. 11 Pour the fibre reinforced
This will provide a screed rail concrete topping ensuring that
3 Place the perimeter Psi-Block® to facilitate the correct depth the concrete is not poured from
at either end of the plot, ensuring of concrete to be poured a height greater than 500mm
blocks are bedded on mortar. to achieve the correct floor and that heaping is kept to a
construction depth. height not greater than 300mm.
4 Psi-Blocks® can be cut to
suit using a proprietary hand saw. 8 Once the mortar has cured 12 The concrete topping
sufficiently and multiple beams can be tamped and floated as
5 Working from one end of have been concreted together, required. Please consult with
the plot use the spacer blocks to the 80mm thick insulation your concrete supplier for the
accurately set out the position of sheets can be laid over the correct installation method.
the beams which will have been top of the floor and cut with a
arranged to suit the location hand saw to suit the layout. Any
of service risers. Ensure that offcuts can be reused within
the beams are placed tight the floor. Any gas membrane
against the spacer blocks. that may be required should be
positioned above the beams
and below the sheet material.

Tips and hints

1. Once the beams have been 3. Scaffolding boards can be used 6. If required, any DPM or gas
accurately set out, the perimeter to hold down the insulation sheet membrane should be installed
Psi-Blocks® and spacers blocks should strong winds prevail prior between the top layer of
can be bedded on mortar and the to placing the concrete topping. insulation and the infill blocks.
coursing blocks can be bedded. This will ensure that any fixings
This will allow the polystyrene 4. Small offcuts of the insulation required for pipework etc. will
insulation and concrete topping can be used to effectively seal not compromise the membrane.
to be installed in one day. gaps around any service openings.

2. Large service openings are 5. Underfloor heating pipes can
best accommodated by placing be accommodated. The standard
a full block either side of the pipe clips can be secured to the
opening and taking out half top insulation sheet material.
the opening from each block.

Hanson Jetfloor | 9

Jetfloor – a cost-effective solution

During the development of our One of the key areas that helped Turner & Townsend
new Jetfloor we engaged the make the difference was the testimonial:
services of cost consultants overall floor thickness particularly
Turner & Townsend who made when compared to a 175mm “We have extensive experience
detailed cost comparisons deep beam and block solution. of housing schemes and
between a range of structural helping to deliver value
ground floor solutions including: The reduced floor thickness with for our clients. We have
Jetfloor will inevitably lead to cost applied our knowledge to
•• Suspended in situ concrete savings through the reduction review the new Jetfloor
of dig and spoil removal costs. product. Certainly given
•• 150 beam and building block typical build requirements
When you add the inherent speed and site conditions the
•• 175 beam and building block of installation and the robust edge Jetfloor system provides a
details it is easy to see how new good cost-effective solution
Their findings clearly show Jetfloor will give housebuilders with the benefit of reduced
that, based on similar ‘U’ value and specifiers cost-effective off site disposal. It would
performance, new Jetfloor is the certainty of compliance with certainly be an ogpnitdiliouBnybthdearituqwer eerehW
most cost-effective solution. the latest requirements of part would advisenooitualruscnildienunostsroftsonoitalugeR
L of the building regulations. consider on housing projecstesh.”siniF

Comparison diagram tew suounitnoC
redliub yb ratrom
175 Beam and Block Finished floor level rebmac pu ekat ot

Finished floor level

410 150 300

560 450

Increased dig and spoil removal costs 150

For more information
on the Jetfloor system
Tel: 0870 609 7094

Email: [email protected]

Or go to: hansonjetfloor.co.uk
to watch our installation video

10 | Hanson Jetfloor

Design Solutions

Hanson also produces a wide range of related solutions including
Hollowcore, stairs and landings and conventional beam and block.
This is complemented by a wider range of design solutions that
includes Retaining Walls, Box Culverts and Omnia Bridge Deck.

Hollowcore Retaining Walls

Structural solution for apartments Engineered solution for retaining
and commercial buildings. structures and materials storage.

Beam and Block Box Culverts

Ideal solution for first floors in houses. Wide range of applications including watercourse
management and water attenuation.

Stairs and Landings Omnia Bridge Deck

Standard and bespoke stairs Permanent formwork for bridge structures.
for a wide range of applications.

Hanson Jetfloor | 11

Hanson Cement

Our companies and products

Hanson UK is the leading supplier of heavy building materials to the UK construction industry.
We are split into three business lines – Hanson Cement, Hanson Building Products and Hanson
Quarry Products. Hanson UK is owned by the HeidelbergCement Group, which employs over 53,000
people and operates worldwide. Hanson UK employs around 4,200 people across over 300 sites.
For detailed information on all areas of Hanson and our products visit: hanson.com/uk

Hanson UK products and services

Concrete Aggregates Asphalt Contracting
•• Ready-mixed concrete •• Sand •• Hot rolled asphalt •• Highway maintenance
•• Ready-mixed mortar •• Gravel •• Stone mastic asphalt •• Road surfacing
•• Dry silo mortar •• Crushed rock •• Asphalt macadams •• Civil engineering
•• Screed •• Recycled aggregates •• Wind farm construction
•• EcoPlus •• Waste to energy facilities
•• MOD works
Bulk cement products
•• Grey Packed products
•• White •• Cement
•• Blends
•• Regen (GGBS) •• Ready to use concrete, mortars,
asphalt, aggregate and sand

Bricks Blocks Precast concrete Cladding and Other products
•• Clay bricks and •• Aircrete •• Retaining walls render systems and services
•• Culverts •• Cladding and •• SUDS
brick specials •• Aggregate •• Barriers
•• Floors render systems •• Geothermal
•• Clay pavers •• Stairs
•• Structural walls •• External Wall ••
•• Bespoke clay •• Basements Insulation (EWI)
products •• Off-site solutions •• Roofing
•• Structural EWI
•• Chimneys
•• Fastbrick ••
•• Brick and block

laying contractors

Hanson Precast Products 09/2013/2623MICH

Hanson House, 14 Castle Hill, Maidenhead, Berkshire SL6 4JJ

hansonjetfloor.co.uk