Historic buildings in Machynlleth and Llanidloes are set to get new leases of life with plans hatched for restoration and improvements at the towns’ most iconic sites.

A scheme has been submitted to add disabled access and disabled toilet facilities at the Owain Glyndŵr Centre on Maengwyn Street in Machynlleth as part of a wider review of improvements at the 15th century building, believed to be home to Wales’ first-ever parliament, while Listed Building Consent has been granted to finally begin structural repair work on the Old Market Hall in Llanidloes.

Powys County Council has been overseeing repair works on the Grade I listed Old Market Hall, with the first phase of the works completed earlier this year.

Further structural repairs, which will include the use of new technology to strengthen the stability of the building with anchors, were due to take place in the summer but were delayed ahead of the granting of Listed Building Consent for the work.

The consent was finally granted on 3 October.

The painstaking work to perform repairs to make the early 17th century building structurally sound will include conditions on the type of tools and materials that can be used.

The work will also include new mortar work inside, replacing previous work.

A planning report said: “It is considered that the proposal will improve the historic character of the building by removing inappropriate materials, whilst also seeking to ensure the structural stability of the building.”

The council said the work will “ensure that this iconic building is protected for future generations”.

In Machynlleth, an application has been submitted to Powys County Council for Listed Building Consent for “alterations and improvements to include installation of disabled lift to serve first floor, repairs and upgrade of internal fabric, energy efficiency improvements, internal alterations to provide disabled toilets and external works and improvements” at the Owain Glyndŵr Centre.

Planning documents said the move to add disabled access and toilets foll­owed a review, survey and series of meetings in a bid to improve the use of the building.

The review found “one of the main issues is to facilitate disabled access and WC facilities” at the site, with the addition of an internal lift to link the ground and first floors.

Apart from the new lift, some minor changes are proposed on the first floor to provide additional toilets and a small kitchen for evening events.

New entrance signage and work to link the complex – which is made up of Parliament House, along with a building containing Caffi Glyndŵr, three shops, an old snooker room on the ground floor and meeting rooms above – will also be undertaken.

Double glazing will be added to all the windows as the running costs of the building are “significant” due to its “extremely poor thermal properties”, a report said.

“Toilets are an issue, there is only one ground-floor toilet which is in a poor condition; there is no toilet provision for the disabled,” a planning report said. “There is also a lack of cohesion to the main entrances on the street. The entrance to the institute in particular is unwelcoming and not sheltered.”

The project would be carried out in phases, the report said, and would be expected to take between 18 months to two years to complete.