Work begins this week on a £49m project to build a new emergency department and assessment centre at Wexham Park Hospital.

The plans will create one of the best and most innovative units of its kind in the NHS. Sicker emergency patients will be treated in individual rooms and there will be extra wards above for testing and treating patients who arrive via the emergency department (ED).

It represents the biggest single investment at the Slough hospital since it was built more than half a century ago.

Frimley Health NHS Foundation Trust chief executive Sir Andrew Morris said: "We have been planning this since 2014 so I’m really excited to be starting building work on something that will be a huge asset to the health of local people for decades to come."

The building project has been planned since we took over managing the hospital in October 2014. At the time, funding was effectively secured for a new emergency department. But our ambition to add the assessment units to the plans needed further approval from authorities.

Having the wards located in the same building as the ED will benefit patients and increase efficiency. Dedicated clinical teams attached to emergency and short-term medical care will be able to collaborate better and patients will have quick access to the right wards where the specialist clinicians and equipment will be on hand.

Sir Andrew added: "When we looked in more detail at the design for a replacement ED we realised we had a great opportunity to be really forward thinking and innovative.

"Locating the assessment wards above the new ED will improve the experience and results for patients and will allow us to provide a higher quality of care more efficiently.

"Putting these important wards together also frees up space on the rest of the Wexham Park site so we can move some other services into better buildings and locations."

The 36 individual rooms in ED will provide better safety, privacy and infection control. The design will be similar to our other emergency department that was rebuilt at Frimley Park Hospital near Camberley in 2012. The floor above ED will test and treat patients who can go home within 24 hours and the second floor will be for short stay assessment and treatment for up to 72 hours. Following this, patients will either be discharged or admitted to another part of the hospital.

A third floor will house offices, staff rooms and plant equipment for the building.

The building is due to be finished in late 2018 and the space vacated by the current ED will be converted into a better environment and location for other hospital services.

Building work is already in full swing on another part of the Wexham Park site where £10m is being spent improving maternity and gynaecology services. Work began in October and the next phase of the project will see the labour ward upgraded with en suite facilities in each room.