Toby Newell
Member
- Messages
- 1,635
- Location
- Surrey
That is his official title. Someone mentioned I should consider training as a CO, this is why not. How long do you think I would last in Hackney? Spot the mistakes here...
> On 27 Jan 2016, at 19:20, Xxxxxx Xxxxxx <xxxxxxxxxxxxxxxxxx> wrote:
>
> Hello. In summer 2014 you were very helpful over the phone, responding to an email which I had written (below) regarding repair of the timber floor in our Grade 2 listed Queen Anne house. We are now at the point when we want to take some action. Yesterday the Listed Building Officer for the borough paid a site visit and advised:
>
> Analysis of the Proposal
> The following conservation comments are offered on the proposals:
> The proposals relate to the floor in the ground floor entrance hall and front and rear rooms. The floor is an exposed timber floor consisting of approximately 7 inch wide plain square edged boards, fixed with modern cut floorboard brad nails. The boards appear to be about ¾ inch (18mm) thick and appear to be of spruce and are stained a very dark brown, almost black. The floor is mixed in terms of significance, with some areas very likely to be late 17th or early 18thcentury boards; other areas may be later and there are a few areas (particularly in the hall) which are modern plain boards.
> The floor has a number of problems. It is not flat, with various slopes, mainly from the front to the rear of the building. It also undulates, with higher and lower areas. Neither of these features are problematic in use and are part of the character of an old house. Other features such as the dark staining, split boards, gaps, holes and poor quality sealing of gaps by rodent destructors are less satisfactory.
>
> Advice
>
> The following advice is offered to assist the applicant:
> In my opinion, the floor would benefit from some attention but is capable of being repaired to a satisfactory state. These repairs could include lifting and relaying the floor to remove or reduce gaps, refixing loose boards, inserting battens to improve the flatness and levelness of the floor, inserting a wire mesh beneath the floor to prevent rodent intrusion, replacing split or seriously damaged boards (particularly modern ones) with suitable reclaimed timber, sanding and refinishing the boards and introducing a modern floor covering.
> Provided these works were performed in a sensitive and non-intrusive manner, Listed Building Consent would not be required since the works are essentially a repair. Under no circumstances should all the boards be lifted over a large area at once since the floorboards in buildings of this age and type prevent the floor joists from rotating: lifting all the boards at once has the potential to result in the collapse of the building. The boards should be lifted one small area at a time and be numbered or coded in pencil underneath to ensure that, as far as possible, they are returned to a similar position. Floorboards should be re-fixed with cut steel brad nails of the traditional type (not screws).
> It is likely to be possible to sand the existing boards and apply a more appropriate and attractive finish.
> The installation of a fitted carpet or other covering would not require Listed Building Consent as long as the works were reversible and the historic floor remained beneath.
> The installation of a floating engineered timber floor would not require Listed Building Consent as long as the works were non-intrusive, reversible and the historic floor remained beneath.
>
> I appreciate you are very busy. I will ring you in a day or two to see if you might be able to make a site visit to consider this project. Thank you.
>
> Kind regards,
And my second more considered reply... (which failed to ask how did the CO identify the age of the boards without lifting them or seeing the grain seeing as going on width alone I would put 7 in softwood boards at circa 1860. I also failed to mention the impossibility of totally levelling a 400 year old floor and stating that battens were not appropriate, supplementary piggyback joists being the better, stronger option)
Xxxxxx
I was very tired when I wrote that!
Specifically:
1. If it has been implied that there is a danger of catastrophic failure if all the boards are lifted in one go and that the correct method is lifting “small areas” then small areas needs to be quantified. At what point do the boards removed effect the joisted structure by increasing point loads caused by the loss of load sharing members (floor boards) the officer, if he has the professional capability, or a building / civil engineering surveyor should asses the situation and give quantitative guidance on the maximum liftable area and an explanation of the mechanism of the problem.
2. Removing the floor could cause significant unavoidable damage both to the original boards and unrelated structures like lime plaster (if this is the case) removing should actually be the option of last resort.
3. Cut brads are preferable in aesthetic terms but not if their use compromises the efficiency of the floor (loose, creaking and over time cracking) sometimes discrete use of screws holes either filled or left is the only way to securely fit sometimes pest eaten, partially friable boards to joists which may not be in perfect condition due to their advanced age. The use of screws reduces the amount of hammering which can cause shock damage to plaster.
4. You can buy specific mouse wire for use in air bricks, someone must be able to supply that wholesale, how one would fit it, I do not know, if between the joists and the boards the floor may be harder to reaffix securely.
5. If the boards are lifted and remain salvageable they should be archived with fluorescent paint marker on the front and put back exactly where they were lifted and not a “similar position” boards age and dry with the shape of the joists due to the stresses in the structure and so moved boards may cup or bow against their new joist position (joists may be so deformed too) I have done this and have many pictures of a project where I lifted the whole ground floor, new joists were fitted, insulation was installed and the boards put back exactly where were taken from, the floor was a mixture of 30 to 400 year old timber and I supplied reclaimed timber to undertake repairs and when reaffixed it was hand machine sanded, coloured, shellacked and lacquered.
6. Although laying an engineered floor is possible it may not be advisable if the floor is very uneven and has large amplitude undulations, the top floor will show cracks, move excessively and eventually the tongues may break, I have seen this in many properties and it causes problems with refinishing too.
7. Your boards apparently are very old, at 18mm they are also quite thin. Load bearing floors are currently specified at 22mm nominal value and so after sanding to remove the dark stain the boards are likely to be at their limit of 16 or 17mm therefore this will be the last possible sanding to the bare wood in the life of this floor, thus the finish has to be a) incredibly hard and permanent or b) a reversible finish that can be stripped chemically, e.g. shellac and waxed finish can be stripped using hot washing soda and fine wire wool, wiped over and rewaxed without mechanical stripping (sanding) I would therefore ask you to consider having a traditional, reversible finish as this can be refinished or stripped without further sanding which can prolong the life of the floor.
> On 27 Jan 2016, at 19:20, Xxxxxx Xxxxxx <xxxxxxxxxxxxxxxxxx> wrote:
>
> Hello. In summer 2014 you were very helpful over the phone, responding to an email which I had written (below) regarding repair of the timber floor in our Grade 2 listed Queen Anne house. We are now at the point when we want to take some action. Yesterday the Listed Building Officer for the borough paid a site visit and advised:
>
> Analysis of the Proposal
> The following conservation comments are offered on the proposals:
> The proposals relate to the floor in the ground floor entrance hall and front and rear rooms. The floor is an exposed timber floor consisting of approximately 7 inch wide plain square edged boards, fixed with modern cut floorboard brad nails. The boards appear to be about ¾ inch (18mm) thick and appear to be of spruce and are stained a very dark brown, almost black. The floor is mixed in terms of significance, with some areas very likely to be late 17th or early 18thcentury boards; other areas may be later and there are a few areas (particularly in the hall) which are modern plain boards.
> The floor has a number of problems. It is not flat, with various slopes, mainly from the front to the rear of the building. It also undulates, with higher and lower areas. Neither of these features are problematic in use and are part of the character of an old house. Other features such as the dark staining, split boards, gaps, holes and poor quality sealing of gaps by rodent destructors are less satisfactory.
>
> Advice
>
> The following advice is offered to assist the applicant:
> In my opinion, the floor would benefit from some attention but is capable of being repaired to a satisfactory state. These repairs could include lifting and relaying the floor to remove or reduce gaps, refixing loose boards, inserting battens to improve the flatness and levelness of the floor, inserting a wire mesh beneath the floor to prevent rodent intrusion, replacing split or seriously damaged boards (particularly modern ones) with suitable reclaimed timber, sanding and refinishing the boards and introducing a modern floor covering.
> Provided these works were performed in a sensitive and non-intrusive manner, Listed Building Consent would not be required since the works are essentially a repair. Under no circumstances should all the boards be lifted over a large area at once since the floorboards in buildings of this age and type prevent the floor joists from rotating: lifting all the boards at once has the potential to result in the collapse of the building. The boards should be lifted one small area at a time and be numbered or coded in pencil underneath to ensure that, as far as possible, they are returned to a similar position. Floorboards should be re-fixed with cut steel brad nails of the traditional type (not screws).
> It is likely to be possible to sand the existing boards and apply a more appropriate and attractive finish.
> The installation of a fitted carpet or other covering would not require Listed Building Consent as long as the works were reversible and the historic floor remained beneath.
> The installation of a floating engineered timber floor would not require Listed Building Consent as long as the works were non-intrusive, reversible and the historic floor remained beneath.
>
> I appreciate you are very busy. I will ring you in a day or two to see if you might be able to make a site visit to consider this project. Thank you.
>
> Kind regards,
And my second more considered reply... (which failed to ask how did the CO identify the age of the boards without lifting them or seeing the grain seeing as going on width alone I would put 7 in softwood boards at circa 1860. I also failed to mention the impossibility of totally levelling a 400 year old floor and stating that battens were not appropriate, supplementary piggyback joists being the better, stronger option)
Xxxxxx
I was very tired when I wrote that!
Specifically:
1. If it has been implied that there is a danger of catastrophic failure if all the boards are lifted in one go and that the correct method is lifting “small areas” then small areas needs to be quantified. At what point do the boards removed effect the joisted structure by increasing point loads caused by the loss of load sharing members (floor boards) the officer, if he has the professional capability, or a building / civil engineering surveyor should asses the situation and give quantitative guidance on the maximum liftable area and an explanation of the mechanism of the problem.
2. Removing the floor could cause significant unavoidable damage both to the original boards and unrelated structures like lime plaster (if this is the case) removing should actually be the option of last resort.
3. Cut brads are preferable in aesthetic terms but not if their use compromises the efficiency of the floor (loose, creaking and over time cracking) sometimes discrete use of screws holes either filled or left is the only way to securely fit sometimes pest eaten, partially friable boards to joists which may not be in perfect condition due to their advanced age. The use of screws reduces the amount of hammering which can cause shock damage to plaster.
4. You can buy specific mouse wire for use in air bricks, someone must be able to supply that wholesale, how one would fit it, I do not know, if between the joists and the boards the floor may be harder to reaffix securely.
5. If the boards are lifted and remain salvageable they should be archived with fluorescent paint marker on the front and put back exactly where they were lifted and not a “similar position” boards age and dry with the shape of the joists due to the stresses in the structure and so moved boards may cup or bow against their new joist position (joists may be so deformed too) I have done this and have many pictures of a project where I lifted the whole ground floor, new joists were fitted, insulation was installed and the boards put back exactly where were taken from, the floor was a mixture of 30 to 400 year old timber and I supplied reclaimed timber to undertake repairs and when reaffixed it was hand machine sanded, coloured, shellacked and lacquered.
6. Although laying an engineered floor is possible it may not be advisable if the floor is very uneven and has large amplitude undulations, the top floor will show cracks, move excessively and eventually the tongues may break, I have seen this in many properties and it causes problems with refinishing too.
7. Your boards apparently are very old, at 18mm they are also quite thin. Load bearing floors are currently specified at 22mm nominal value and so after sanding to remove the dark stain the boards are likely to be at their limit of 16 or 17mm therefore this will be the last possible sanding to the bare wood in the life of this floor, thus the finish has to be a) incredibly hard and permanent or b) a reversible finish that can be stripped chemically, e.g. shellac and waxed finish can be stripped using hot washing soda and fine wire wool, wiped over and rewaxed without mechanical stripping (sanding) I would therefore ask you to consider having a traditional, reversible finish as this can be refinished or stripped without further sanding which can prolong the life of the floor.
