8/14/2019 Part L1B Extensions

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Part L1B Extensions

Is the extension a

conservatory?

Does the area of windows, roofwindows and doors in the

extension exceed:

a) 25% of the floor area of theextension; plusb) The area of any windows ordoors which, as a result of theextension works, no longer existor are no longer exposed?

Does the extension meet the PartL1B elemental requirements for

the provision of thermal elements,

controlled fittings and controlled

services?

Does the extension

meet the Part L1B

elemental

requirements for the

provision of thermal

elements, controlled

fittings and controlled

services?

You do not need to undertake a SAP assessment in order to show compliance with

Part L1B of the Building Regulations.

If the floor space of the conservatory is less than 30m2 then it will be exempt from

the Building Regulations. If it is greater than 30m2 then compliance will be shown

by meeting the standards for new or replacement thermal elements and controlled

fittings as stated in Part L1B, and including independent on/off and temperature

control for any new or extended fixed heating services.

You-have-two-trade-off-options-in-order-to-show-compliance-with-Part-L1B-of-the-Building-Regulations.

1. The thermal properties of exposed walls, roofs and floors, and the thermal properties and areas of glazed openings, may be traded-off

against each other, subject to limits and to the area-weighted average U-value of the extension envelope being no greater than if all the

elemental standards had been met; or

2. A SAP assessment may be undertaken to show that the carbon dioxide emissions of the extended dwelling as proposed are no greater

than they would have been if all the elemental standards had been applied to the extension. This option allows the greatest design flexibility by

allowing you to make voluntary improvements to the original dwelling which can then be offset against the specification of the extension.

A-conservatory-is-an-extension-to-a-building-which:

a) Has not less than three quarters of its roof area and not less than one half of its external wall area made from translucent material; and

b) Is thermally separated from the dwelling by walls, windows and doors with U-value and draught-stripping provisions as provided elsewhere in

the dwelling.

YES

NOYES-

NO

NOYES

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 A one-stop-shopfor all your Part Lrequirements.

FAST - we aim tocomplete every SAPcalculation within 48hours.

RELIABLE - we only usehighly experienced SAPassessors.

VALUE - we aim for everyquote to be the mostcompetitive, with largediscounts available formultiple orders.

P

P

P

No lengthy forms, we offer a single point of contact for the entire project.

Let us take the stress out of Part L

What is SAP?

The Standard Assessment Procedure (“SAP”) is the

Government’s approved methodology for calculating theenergy performance of dwellings.

How long does a SAP assessment take?

We aim to complete each SAP calculation within two workingdays from the point of engagement.

How much does a SAP assessment cost?We strive to ensure each quote is the most competitive in themarket, offering you real value for a quality service. Factorsthat will affect the cost of a SAP assessment include the sizeand complexity of the dwelling. Call now for an instant quotefrom one of our qualified SAP assessors.

What happens if my dwelling fails the SAP assessment?

Our SAP assessors will be happy to provide you with a freeconsultancy service, advising you on all necessaryamendments to ensure a PASS EVERYTIME.

If you build an extension where the glazing isover 25% of the floor area, then we canundertake a SAP assessment to demonstratePart L compliance.

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How can Energytest help me?

We can provide an economic and feasible solution to ensure your extension complieswith Part L1B of the Building Regulations, regardless of how much glazing you wish toinclude in the specification of the extension.

Options that will benefit the overall energy performance of the extended dwelling include: 

• Using materials with low thermal transmittance (U values) for the construction of theextended building envelope;

• Including high levels of thermal insulation within the extended building envelope;• Adding thermal insulation to the existing building envelope;

• Improving the air tightness of the dwelling and the characteristics of its ventilationequipment;

• Improving the efficiency and controls of the heating system(s);

• The efficiency of the fuel used to provide space and water heating, ventilation andlighting; and

• The inclusion of low or zero carbon technologies, such as photovoltaics or groundsource heat pumps.

What do I need to provide to the SAP assessor?

• Floor plans, including building elevations and sections;

• Details of the buildings location and orientation;

• Specification for the construction of all floors , roofs and external walls;

• Specification for all windows and doors within the buildings external envelope,including frame material, width of gap (if multiple glazing) and emissivity of glass;

• Details of all heating, ventilation, air conditioning and lighting within the building;

• Hot water system specification, including calorifier size, details of any insulation to thecylinder and pipes, and associated controls;

• Full details of any fixed secondary heating, cooling, and hot water systems; and

• Details of any low or zero carbon technology, such as solar hot water, photovoltaics,ground source heat pumps, or wind turbines.

No lengthy forms, we offer a single point of contact for the entire project.

Let us take the stress out of Part L