garden timber framed music room UK

Hi All I have been reading lots of posts on here and also rod gervias book on studio design and hope people can give me some pointers on the building i am planning before i spend any cash. I am a guitarist/songwriter and electrician i have been in bands during the last 15 years and am planning on building a music room /garden room in the small space i have at the end of my garden with the help of a joiner friend who has a building company. primarily it will be used by myself to play and store my equipment guitars /amps a small PA for vocal/acoustic guitars only and a piano. It will be used for songwriting /jamming and somewhere to chill out in. I plan on investing in a mac or pc based system to produce some demos also but not pro studio level gear to begin with. there will be no drumkit or bass amplifier so no 110db rock band levels to contend with. I dont play particularly loud using my amps and knowhere near stage levels but expect to use the room for acoustic instruments and vocals through the PA around 85db inside. i know i need to take some db measurements to justify this but im looking to achieve a good level of isolation from the outside world inside and vice versa. the nearest neighbour is 15m away. the space i have is approx 6.3m wide by 5-6m long the planning restrictions allow the building to be no more than 2.5m in height and less than 30m2 in floor area. there is a solid brick wall 1.3m high to the right and a breezeblock garage 2.5m high to the left behind the hedge (see picture below) I want to make the most of the space i have and intend to use one room and build the outer shell 5m x5mx 2.5m high. the outer shell will be a timber framed cedar clad type similar to the picture below. Concrete base 4-6" deep tanalised timber floor /insulation/ply/oak flooring The exterior walls from outside in will be cladding/airgap/membrane/exterior ply/studwork/insulation. The exterior roof will be a PIR rigid thermal insulation panels with metal outer lining and internal coated metal skin within this outer shell i plan to build the second leaf walls as follows studwork/insulation/2 layers plasterboard/plaster skim the internal ceiling resting on this studwork to be plaster skim/2 layers plasterboard /resilient chanell/studwork/insulation. The exterior will have a aluminium bifold triple glazed/acoustic glazed door approx 2.0m wide x 2.05m high no windows so it looks like a garden room and can be used now and if i ever sold the property. my budget is £8000 ish my questions: originally i want to use the space as 1 room to get the most out of the space i have and wondered if there is any solution using screens or panels that could be moved into place over the door to improve any sound loss? does the design sound feasible? any comments would be appreciated. many thanks

Hi "crashturtle". There is an announcement at the top of the forum about what to do to assure getting as many responses as possible. Please read that: it is the forum rules for posting (click here). You seem to be missing a couple of things from there! :) - Stuart -