If it were me I think I'd consider building a pelmet on the face of the 'architrave' to house the blinds, the face of the pelmet running paralell with the architrave.
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If it were me I think I'd consider building a pelmet on the face of the 'architrave' to house the blinds, the face of the pelmet running paralell with the architrave.
Bendy plywood or similar (its a thing, google it). It's possible to make your own to save buying the ready made stuff if you put a series of cuts in the rear of the board, you would need access to a table or mitre saw or similar though. Might be worth considering.
You would need to keep the distance between the new pelmet and the architrave to a minimum to reduce any twisting under the weight of the blinds.
What type of blinds are you fixing?
Roller, Venetian, vertical, Roman?
Or 3mm MDF is quite a popular choice for this by all accounts, after googling, the whole thing ideally made up and then hung on the wall rather than making it insitu.