Smart Engineering for Residential Developments

Meet the building services engineer who’s delivering some of Ireland’s most high performing schemes.

As residential schemes push higher and denser across Ireland’s towns and cities, there’s pressure on every square metre - and every decision.

One piece of advice for developers?

“Get your M&E team in before planning,” Barry says. “Otherwise, you’re designing yourself into a corner - and undoing it later costs time, money, and options.”

Heating strategy, plant space, sustainability targets, metering access - the services strategy isn’t just a detail. It defines how a building will perform, how long it will last, and whether it stays compliant with regulation five years from now.

But too often, the opportunity to influence that strategy is missed.

“If we’re brought in after planning, the damage has already been done,” says Barry Dunne, Senior Engineer at Metec. “There’s no allowance for plant space, nothing on the roof for PV, no real options. You’re limiting your choices before the project has properly started.”

Early-stage M&E input is essential

Many smaller developments delay bringing in mechanical and electrical consultants until post-planning. But by then, key spatial decisions have already been made - and they can be difficult, if not impossible, to reverse.

“Planning layouts might look fine, but they’re often missing the basics: risers, comms access, space for plant,” Barry explains. “If we’re involved early, we can shape the options. Leave it too late and you’re trying to retrofit solutions into a fixed design.”

Part L of the Irish Building Regulations, updated to reflect NZEB requirements, sets three performance targets for new dwellings:

1. Maximum Permitted Energy Performance Coefficient (MPEPC) of 0.3
   
2. Maximum Carbon Performance Coefficient (MPCPC) of 0.35
   
3. Renewable Energy Ratio (RER) of 20%
   

If M&E engineers are brought in too late, the building may not have enough space or infrastructure to meet these targets.

Meeting these targets:

1. Improves the BER rating
   
2. Makes units more attractive to buyers and tenants
   

Early M&E involvement ensures key energy performance decisions - including heat source, insulation levels, and plant space - are built into the design, not retrofitted later.

Heating strategy starts with scale - and ends with intent

There’s no one-size-fits-all solution when it comes to heating strategy in dense residential schemes. And that’s the point.

“What works for 40 units isn’t what you’d choose for 140,” Barry explains. “You need to find the tipping point - when individual heat pumps stop making sense, and a central plant becomes more efficient.”

To help clients decide, Barry’s team created a comparative strategy model - testing real layouts against cost, plant space, and sustainability performance.

‍“We looked at all the typical systems - individual, centralised, and exhaust air heat pumps - and ran them through our sustainability compliance checks. We could see which required additional renewables for compliance (such as PV panels), what impacts they each had on BER performance, and what space allowances were required. Alongside cost impact, this is the level of initial clarity developers need early on”

It’s not just about compliance - it’s about livability and maintenance too. Especially on local authority and social housing schemes, long-term performance matters.

“Dún Laoghaire-Rathdown, for example, aren’t just ticking boxes,” Barry says. “They’re focused on reducing maintenance calls in the future. So we help them design systems that last - not just systems that pass.”

Tools like Metec’s Overheating Assessments, led by Scott Caldwell’s team, are now a critical part of high-density residential design. These assessments identify risks early - including issues like corridor pipework that can raise internal temperatures above acceptable levels.

Overheating assessments help ensure that buildings remain comfortable and safe during hot weather, both now and in the future, by informing and guiding design decisions such as:

• Determining glazing specification
• Adding external shading
• Improving natural or mechanical ventilation
• Reducing glazing area
• Utilising thermal mass

From model to outcome: BIM + OEM + QA

Design certainty comes from collaboration - and technology. Metec’s in-house teams (M&E, BIM, sustainability) work side-by-side in the same open-plan office, feeding data directly from model to simulation.

“On the Seapoint job, every design team member uploaded their models weekly into a shared environment,” Barry explains. “It meant everything aligned - and the energy modelling from our OEM team was based on real, validated design data.”

How do you ensure the services design doesn’t just meet compliance - but actually enhances the livability and long-term performance of the building?

Ballyogan Square is a clear example.

Phase 1 of this 67-unit residential scheme, delivered for Dún Laoghaire-Rathdown County Council, was built to Passivhaus Standard and certified A1 BER - two of the highest performance targets for residential construction.

The brief went far beyond compliance: Metec was responsible for building lifecycle assessment, remote air quality and energy monitoring, bat-sensitive site lighting, and full M&E design - including a fabric-first approach, triple-glazing, and Passivhaus-certified mechanical ventilation.

Meeting these goals required close collaboration with Van Dijk Architects and Passivhaus consultant MosArt, with Metec advising on layout changes, servicing strategies, and acoustic solutions due to the site’s proximity to the M50.

The result: a livable, low-carbon scheme with robust internal air quality, smart metering, and futureproofed performance, fully aligned with Ireland’s Part L NZEB requirements, the EU Energy Performance of Buildings Directive (EPBD), and the Level(s) sustainability reporting framework. - with Phase 2 now fully designed and tendered.

These outcomes also strengthen the project’s ESG profile, positioning it for green finance eligibility and readiness for future reporting obligations under frameworks like the Corporate Sustainability Reporting Directive (CSRD).

Planning a dense residential scheme?

‍The best outcomes start early - with a services strategy designed to deliver performance, not just compliance.

Before you start your high density residential project, ask yourself these 3 questions

1. Have we engaged M&E before planning/ Have we engaged the Metec team?

2. Is our heating strategy optimised for scale and compliance (Part L/NZEB)?

3. Have we performed an overheating assessment?

For more info - get in touch with Barry: https://www.metec.ie/people/barry-dunne‍