Self-Build Cashflow in Ireland — How the Money Flows Month by Month

Self-build cashflow in Ireland: deposit at month 0 (10% of build, typically €25k–€60k on a €500k build), build cost over 9–15 months (stage payments tied to milestones), snag and final drawdown at months 12–18. Plan for €6k–€15k mortgage interest during the build (4.5% on drawn amount). Plus the 13.5% VAT you can't reclaim immediately (until the next VAT return). Most self-builders underestimate the cashflow. Keep 3 months of build costs in reserve as a cash buffer. The biggest cashflow spike is the second-fix period (months 9–12), when kitchen, bathrooms, and flooring all hit together.

TL;DR

• Self-build cashflow: deposit at month 0, build cost over 9–15 months, snag and final drawdown at months 12–18.

• Plan for €6k–€15k mortgage interest during the build (4.5% on drawn amount). Plus the 13.5% VAT you can't reclaim immediately.

• Most self-builders underestimate the cashflow. Keep 3 months of build costs in reserve as a cash buffer.

When this matters most

You're planning the cashflow for the build.

When this doesn't apply

The build is finished.

Frequently asked questions

When is the most expensive part of a self-build?

Second-fix period (months 9–12 on a typical build). Kitchen, bathrooms, flooring, tiling, painting, electrical finish. All hit in the same 2–3 months. Plan for the spike.

How much cash buffer do I need for a self-build?

3 months of build costs. €30k–€50k on a typical €500k build. The buffer covers mortgage interest, VAT gaps, and unexpected overruns.

When does the final VAT reclaim happen?

At the end of the build, when you file your final VAT return. Can be 12–18 months after the first VAT spend. Plan for the gap.

Sources

Revenue Commissioners, VAT on residential property. https://www.revenue.ie/