Yes. En-suites are one of the most popular additions to an attic conversion, and in many cases they turn the attic into a proper self-contained main or guest bedroom. As a rough guide, adding an en-suite costs around €8,000 to €15,000 on top of the conversion, depending on the layout, the fittings you choose, and how far the plumbing has to travel.
The main things to plan are soil pipe routing for the toilet, a water supply for the basin and shower, and proper ventilation to remove moisture. The single biggest cost driver is distance from existing plumbing. If the en-suite can sit near a bathroom or soil stack on the floor below, the pipe runs are shorter, the work is simpler, and the cost stays lower. Positioning also lets us use the awkward parts of the attic sensibly, for example tucking the shower under a section of sloped ceiling where full standing height is not needed.
Ventilation is not optional; a bathroom in a warm insulated roof needs mechanical extraction to protect the structure and finishes. We size that into the design from the start rather than bolting it on later.
- Position the en-suite near existing plumbing to reduce cost.
- Plan soil pipe, water supply, and extraction together.
- Use sloped areas for the shower to save headroom elsewhere.
For more detail see attic conversions with an en-suite and the en-suite cost breakdown. If you want a figure for your own house, book a free assessment.