Cleaning a polytunnel

The polytunnel needs to have a clean inside and out as it was full of weeds which were almost touching the roof and it doesn't look as if it's been cleaned for years. With a greenhouse I would use Jayes Fluid (other makes available). Do any of you poly owners clean the inside and outside of your and if so what do you use.

I use warm soapy water and a soft broom....pleasantly shocked when I first did this as loads of light and seethrough. It came with the house.

Thank you Grinling, was beginning to think no one cleaned their polytunnels     it's what we ended up doing anyway, using warm soapy water and our caravan brush, it came up sparkling, almost like a new one