The visitor centre is due to open this summer following extension of a thatched barn next to iron-age Double Dykes settlement. More than a million people visit the reserve every year.
A natural turf roof planted with grasses will blend in with the natural surroundings, offer insulation and soak up rainfall. Modcell walls, timber frames infilled with straw bales will form a thick insulating cocoon. Herbert Drew and Son is the contractor.
Meanwhile 16 photo-voltaic panels will generate electricity to save around £1,000 a year in energy bills. Once open the new centre will offer an exhibition area, classroom and shop. Landscaping will form outdoor learning areas and a wildlife garden.
The centre will cost around £1m, with £300,000 from developer contributions, £432,000 from the Heritage Lottery Fund and £300,000 from the Landfill Communities Fund via Canford Environmental.
Bournemouth Borough councillor Rod Cooper said: "The eco-friendly element to this building is vitally important to ensure it not only blends in with the natural surroundings but is also energy efficient and has minimum impact on the environment."
The centre will be a community-run project involving more than 50 trained volunteer heritage wardens and 10 apprentices and the council’s countryside team.