Work constructing the £450,000 building at Cuerden Valley Park is now entering its final phases.
“The building is timber-framed with walls made of straw bales, old car tyres for foundations, and a cedar shingle roof,” said trust manager Simon Thorpe.
“It will have a ground-source heat pump with underfloor heating, electricity supplied by solar panels on our barn and rainwater harvesting to feed the toilets.
“However, perhaps the most exciting aspect is the stunning panoramic view from the new café over the valley to the River Lostock below.
“There are many people who can’t wait to visit and we’re pushing hard to get it finished in time for October half term week.”
The Park Trust is hoping the project will become the first in the UK with no concrete, cement and no PVC plastic.
It also has a ban on other materials which are considered harmful to human health or the environment.
It means the special visitor centre and cafe would achieve the international Living Building Challenge standard, which started in USA.
Construction started in 2015 led by Park staff and volunteers and suffered some initial delays due to the complicated nature of the design.
In recent weeks the cedar shingle roof has been completed and bespoke guttering installed.
Lime plaster work has been carried out by a Fylde conservation specialist, and volunteers are finishing window sills and the detailing.
Work has started putting straw into the floor for insulation and the sewers and water supply are being connected.
The project has been by funded by Lancashire Environmental Fund, Veolia, both Chorley and South Ribble Councils and many donations from supporters of the Park.
Cuerden Valley Park Trust held a competition to come up with a name for the café last year but it is being kept under wraps for now.