The floods currently affecting part of the country have forced Brown Builders’ Merchant to temporarily shut its Chequers Road site until further notice.
The flood happened during the night of Friday to Saturday and the damages have been estimated to be over £250,000.
Drone footage posted on the merchant’s Facebook page shows the business’s flooded yard in the misty morning light of Saturday morning, materials floating randomly.
Still images posted on Sunday show the damage inside the building and in the offices of the company.
Another video from Saturday shows an employee explaining that the premises are under 4 to 5 foot of water and that staff had not been able to access the site at the time. He also apologises for not being able to fulfil scheduled deliveries and for any inconvenience.
The water appears to have now subsided and the clean-up was still going on on Monday.
Brown's Marketing Manager Edd Parlato told the Derby Telegraph: "We stood on the side of the A52 which was shut on Saturday and the water was level with the windows in the offices.
"When the lads left on Friday some of the drains were bubbling, but we've never seen flooding like this before so they didn't think anything of it.
"They put sandbags high on the shutter doors and all the doors into the building, but the flooding was about 3ft over the sandbags."
When the team finally entered the premises on Sunday morning, it found that "the water level was the same inside as outside, 4ft of water had flooded through, and anything below that level in the shop has been ruined.
"Our offices are on the ground floor so every computer and phone isn't working.
"None of the forklifts which were in our warehouse work, and we don't know if the lorries are going to be recoverable.
"It is hard to put a number on it, but we're probably looking at upwards of a quarter of a million just in stock damages.
"Then you've got computers, phones and the cost of repairing the infrastructure, like the carpets and flooring."
Browns had only made Chequers Road its main operating site in November, last year, reserving its Nottingham Road site for plumbing and landscaping.