Planning for NZEB: Tipperary County Council Planning Agents

Seminar

Paula Gallagher,

Tipperary Energy Agency

• Legislative changes here and coming.

• What is NZEB?

• Key changes to building performance

• How to achieve cost effectively

Contents

2020 NZEB

2011 Part L

2008 Part L

2006/2 Part L

1997 Part L

1991 part L

Average Irish House (329)

Typical Rural Stone Dwelling

Progression of Part L & BER

Impact of Part L on Energy Consumption & Cost

20

11 P

art

L

20

20

NZ

EB

“a building with very high energy performance where the nearly zero or very low amount of energy required should be extensively covered by renewable sources produced on-site or nearby” EC Directive 2010/31

Not: Passive house/ Leed / Bream etc (Proprietary standards, varying definitions)

In practice (domestic):

- Careful orientation and built form

- Low U Values (0.15-0.18)

- Heat pumps and PV

- Solar Shading/ Management

NZEB

• MEPC dropping from 0.4 to somewhere around 0.305

• MCPC dropping from 0.37 to 0.302

• BER likely around 45-55 kWh/m2

• 20kWh/ m2 of Renewables (i.e. near 40-60% of energy)

• Achievable only with:– Good Design

– Heat pumps with high Co-efficient of performance (c. 50% of market in 2017)

– PV.

– Certified airtightness with MVHR

NZEB Domestic:

NZEB: Public Building (Fabric)

NZEB: Public Building (Services)

- Gain energy from the Sun in winter

- Keep it out in summer.

- Keep heat in the building

- Insulation

- Airtightness

- Designed to not fluctuate in temperature.

- Add energy very efficiently when required.

- Use energy only when required.

Key Principles

- Gain energy from the Sun

- Large windows on south side

(summer shading)

- Small windows on North

- Can reduce energy consumption by

10%

- Thermal Mass to absorb heat and

store it until evening

- Prevents overheating/ cooling

- More comfortable atmosphere

- Concrete, stone, clay, screed

Passive Solar Design

- Reduce External surface area Vs Volume

(avoid sprawling designs)

- Saves on build cost & energy use

- Balance between aesthetics & Function

- Old pantry’s used to be on north side of

houses…

- Keep store rooms, bathrooms, halls, guest

rooms on north side ( 18 ْ◌°C)

- Kitchen, living area on south side (20°C)

- 20% Savings with Less cost!

Layout/ built form

Thermal Bridging

• The elimination of heat conducting bridges around openings, wall joints etc.

• Usual area where Mould appears in older houses

• Approved construction details required to eliminate www.environ.ie/en/tgd

• Dealt as multiplier in DEAP => Cost effective way to achieve good BER.

Source: DOEHLG, 2008

Wall types• Wide variety of low energy wall types

being used

• Principles to watch out for:

• Low U value (High Insulation)

• Thermal mass on inside

• Low thermal bridging

• Will be 400mm minimum to reach < 0.2

Many Different Wall Construction types:

•Timberframe with

• cellulose

• cellulose and hemp

• firmacell and cellulose

• Hempcrete

• fibre based (glass,wool etc)

• a new one every week

• with masonry exterior (traditional)

• Traditional Cavity wall with 150mm/

200mm PIR

• Exterior (EPS) Insulated block on flat

• loads of others!

Air tightness• Maximum permitted: 3-5 M3/(h.m2) ~ 0.15-0.25 AC/h

• Mandatory blower door test for one off & will require re-

education of all building professionals & trades.

• Air-tight houses have bad reputations

• Controlled ventilation Vs leaky

• Designed to give sufficient air for occupants

• Mechanical Heat Recovery Ventilation requires air

tightness.

• Huge effect on Energy performance & BER if used with

poor air tightness

• The Most Important Change on Site!The “enemy” of Air

tightness

Renewables• Mandatory requirement to have a “extensive level” of Renewables

• 20 kWh/m2/yr of heat energy or 8 kWh/m2/yr of electrical energy

• Heat pump to UFCH or LT radiators: 12-15 kWh/m2 (5-8kW)

• PV 2kW/ 250m2 = 15

45

49

104

105

115

116

118

127

0 25 50 75 100 125 150

All of the Above with HP

All of the above (Orientation, built form, Passive Uvalues & Air Tightness),

Change to 2 story

Hi Spec boiler, stove & controls

Upgrade U value's and Air-tightness

Orientation for Max Solar Gain

RE supply increased (max Solar Thermal Panel)

2008 Part L single story

BER (kWh/m2/annum)

Descri

pti

on

of

Up

gra

de

Typical Upgrades from 2008 Regulations

A1 A2 A3 B1 B2 B3

Contacts

Tipperary Energy AgencyCraft GranaryChurch StCahir, Co. Tipperary

Paula Gallagher

T: 052 43090

F: 052 43012

E: paula@tippenergy.ie

W: www.tea.ie

Thank you.