Advice on bouncy sagging Victorian floor...

[Chughesuk]

My wife and I have just bought a second floor apartment in an 1850s built Victorian house. We had a structural survey done before we moved in and specifically asked the engineer to check the floor substructure - since we wished to move the kitchen into what is currently the living room.

He did and in his report he mentioned the joists were 175x65m at 400mm centres and that it would be fine to support the weight of a a kitchen. The room is 5.5m x 4.5m with the joists running 5.5m span.

Since moving in we have increasingly noticed that the floor sags towards the middle and has some bounce - when you walk around the floor, bottles in the corner of the room rattle together... I have been searching the internet recently and it looks to me that the joists are undersized, which is typical of this type of property.

My question is:

1) should the structural engineer not have mentioned the sag or bounce in his report? And was he right to say that the joist size is fine?

2) if we wanted to level and stabilise the floor would the best way be Sistering the joists? If so would you use the same size timber or larger?

Thanks for you advice in advance...

 

[catlad]

If you do not own the floor below then you are going to have difficulty.

 

[ree]

1. Did you make your request specific and in writing - and did the Surveyor reply in writing in his report or an appendix to that report?

Was the Surveyor "your" Surveyor, or a mortgage Surveyor?

However, if the sag and bounce is so obvious, and you are an upper floor flat, then one would have reasonably expected the Surveyor to have noticed the floor condition.

How did he determine the section of the joists? Did he note the joist section, and length of the span?

Can you view a joist tail as it sits in a wall pocket, and could you determine if the joist is wedged firmly into the wall or loose and free?

Is that a 5.5m clear span with no intervening supporting wall or partition below?

2. Sistering would require more info which would involve opening up part of the floor - there are a number of methods for sistering.