房子的damp问题

看了一套房子,之前买家做了Survey发现了Damp 就不买了,中介提供了 一份 Damp treatment 公司给做了report and quotation,是这样写的:

EXTERNAL OBSERVATIONS FROM GROUND LEVEL
EXTERNAL DEFECTS
Hollow cracked and de-bonded external render was evident to the rear elevation of the kitchen.
The surrounding external ground levels to the front and side elevations are high in relation to the property’s internal floor construction.
Ground levels abutting the walls should be reduced to a minimum of 150mm below damp proof course levels. These works should be carried out by your builder under separate contract.

INTERNAL OBSERVATIONS
Unless otherwise stated our inspection of internal areas was restricted to the ground floor only, and is limited accordingly.
Where our inspection was restricted due to fitted kitchen units and appliances, wall tiles, dry linings, feature fireplaces, built in cupboards, heavy furniture etc. our recommendations are limited accordingly and further damp and decay may exist which has not been included in this inspection.
At the time of our inspection visible signs of dampness, supported by moderate to high WME relative scale moisture profile readings obtained using an electronic moisture meter, indicated the presence of dampness to:-

Front Room
Front and side external walls up to 1m high.

Rear Dining Room
Side and rear external walls up to 1m high including other side of the rear wall in the utility room.

Utility Room
Right hand wall where salting plaster is visible including the other side up to the kitchen units up to 1.2m high.
This is possibly due to apparent damp and /or salt contaminated plaster or an apparent possible breakdown of any existing damp proof course or both of these causes. The causes of apparent dampness are within the limits of diagnosis allowed by non -destructive testing.

Other possible sources of dampness are due to external defects noted above.
All timbers adjacent to damp walls must be considered to be at risk from fungal decay.

PLASTER & SALTS
As the moisture rises from the ground into a wall, it carries with it soluble salts which may be deposited in the wall fabric and plaster, as the moisture evaporates. Certain of these salts, in particular chlorides and nitrates, are hygroscopic; that is they are capable of attracting and absorbing moisture from the atmosphere when the relative humidity is high.

修理的意见是:
1/ Remove the existing skirting boards as required to undertake the treatment works, and re-new upon completion.
The internal surfaces and bottom edge will receive a liberal coating of timber water repellent prior to fixing, to extend the life span of the timber.

2/ Hack-off and remove existing plaster from the areas and heights listed above, and clear resultant debris from site。

3/ Install a chemical damp proof course incorporating our Diffusion Process to those walls listed above. Our damp proof course can be installed (subject to access) in solid walls from one side only of the wall to be treated, causing the minimum of disturbance.

4/ Supply and fix a protective Flex Membrane to the utility/kitchen wall 1.2m high.
This Membrane is a watertight low profile membrane for protection against moisture ingress. The membrane is based on a 2mm thick polypropylene sheet, and has a grey non-woven fleece on both sides . The two fleeces ensure a good adhesion to the wall by means of a special adhesive as well as allow for plaster to the surface.

5 / Re-plaster directly on to brickwork using Tarmac Limelite renovating plaster or using Hardwall plaster on to the Flex Membrane.
After re-plastering, hairline cracking of the setting coat may occur. This will not present a problem regarding the efficiency of the new plaster and should be made good when decorating.

It will be seen from our specification that we have included for hacking off existing plaster. In hacking off plaster it is not unusual for dust to find its way to the remotest parts of the property.
We will take the precaution to minimise this nuisance where practical within the immediate area of our work but we respectfully suggest that you should also take some precautions to protect furniture and the like elsewhere in the property.
No responsibility will be accepted by PRESERVA-CSS for cleaning or any damage caused by dust.

6/ Timber Floors
Dining Room
There is considerable movement in the floor which could be due to fungal decay.
We have therefore enclosed an estimated cost for the worst case scenario which is a new floor and air bricks.

报价 处理以上1-5项 £2100+VAT 处理第六项 £1600+VAT

我们之前没有遇到过Damp的问题,没有经验。想请教大家:

1.这些问题严重吗?是必须现在就要做的吗?房子是老房子。第六项是不是需要做?公司说要揭开地板检查后才能知道是不是需要做。£1600+VAT是最坏的状态下全换需要的价格。
2. 按照报价做完这些能不能解决问题。公司说是有20年质量保证
3. 是不是需要另外找builder处理外墙?大概会有多少钱?
4. 房主说不再接受任何降价,如果要求降价要重新放回市场。房子位置不错,不想放弃,但是如果这个Damp问题很严重,维修费用高,未来预期很多维修,我们就得慎重考虑了。

初次遇到damp问题,请各位不吝赐教!跪谢!

内部问题已经告诉你如何处理了,1000多就能fix的问题不算什么问题,这就是卖家不降的原因。

外部问题主要是改善damp proof course的问题。

谢谢成龙大哥快速回复。
光内部换地板的话不到两千还好,再加上处理外墙的话,又是两千多。又不能只做地板,不处理damp cause. 处理完damp, 还要刷墙, 降低墙外的地面还有另找人做。觉得这样花费有点大, 所以有些纠结。