Matt Trueman: BAC is a building worth grieving and giving for

We now know the extent of the damage – much less than it might have been, and yet still leaving such a hole at the building's heart. The Grand Hall has been lost and the rooms beneath it, Lower Hall, all but destroyed. Both spaces were in the very final phases of a large-scale restoration project – 95% complete – and staff, all safe, thankfully, had moved back in.

Firefighters managed to prevent the fire spreading to the front of the building, meaning two-thirds of the Old Town Hall remains intact. Shows were back onstage by Saturday night and, as artistic director David Jubb confirmed, the next stage of the Transformation Project can go ahead as planned.

What was extraordinary, though, was the force of feeling, as shared by so many people. Time and again, I saw the BAC described as a home – for audiences every bit as much as for artists, and for the local community as much as the arts one. People get married in the Grand Hall, don't forget. Others take their accountancy exams there or let their kids bounce around in its Bees Knees play-space. Artists live, rent-free, in its basement. Its café is always open. McFly made a music video there. Ed Miliband gave a key election speech there. In less than three days, public donations have passed £50,000.

'Battersea Arts Centre has put every inch of its home to use'

I shan't lay out what the BAC means to me – though I did suddenly remember that my first ever crush landed in the building, watching a production of The Sound of Music aged 11 and feeling like my chest might burst – because that's not important. What's important is what it means for us, collectively. The motto on the Lower Hall's ceiling says it all: 'non mihi, non tibi, sed nobis'. Not for me, nor for you, but for us.

I have spent the weekend destroying Britain's theatres in my head and, in all honesty, I can think of very few that would engender the same strength of feeling – either personally or collectively – as Battersea Arts Centre. The Old Vic for its sheer sense of history and the footprints on its stage. The Royal Court because it so clearly stands for something, the nexus of new writing. Shakespeare's Globe as something so unique and, frankly, ludicrous that has, against all the odds, proved itself to work. The Watermill in Newbury, a little snug of a space with its wooden waterwheel and its old corn chutes still intact. The architectural oddity of the Royal Exchange.

Most theatres, taken as buildings, aren't so irreplaceable. We'd feel their loss as assets and as symbols, of course, but less so as agonies or grief. Even a building as iconic as Denys Lasdun's National Theatre could, I think, be replaced with something else if necessary without an overwhelming loss of organisational identity. It's so easy for theatres to feel like playgrounds of privilege; resources for individual artists and audiences to make work and watch, to play and explore.

Not so Battersea Arts Centre, which has put every inch of its home to use. Offices go, cheaply, to independent companies. Artists use rooms to scratch shows. The bar-café and kitchen provide jobs to locals that might struggle to find them and the place remains loyal to its own. It had recently agreed a partnership with Wandsworth Museum, extending its own rent-free agreement with the council to encompass another local service. Battersea Arts Centre is a custodian of its building.

Theatre is more than bricks and mortar, of course, but the very best make something of their host spaces – make more of their materials. They turn them them over to public ownership: not for me, nor for you, but for us.

You can donate to the Battersea Arts Centre via the National Funding Scheme here. You should. It's all of ours, after all.