This article builds upon our earlier discussion on License to Alter Application: How to Obtain Permission from Your Freeholder and takes a more in-depth look at one of the most common questions regarding changes to leasehold properties, particularly flats.
For readers short of time, the key considerations for adding timber flooring to a leasehold property are:
Most leasehold agreements specify that certain areas must remain carpeted and often state that approval to install hard flooring will not be granted. Alternatively, some leases may allow changes to hard flooring with provisions, such as reinstallation of carpets if neighbours complain about noise. Others may permit hard flooring under the condition that the acoustic performance of the floor is not compromised.
The desire to transition from carpet to hard flooring may stem from aesthetic preferences or changes in apartment layout, such as converting a separate kitchen into an open-plan living/kitchen/dining area, aligning with contemporary living trends.
The original intention of these clauses was to ensure that the leaseholder did not simply remove the carpet and underlay laid on the timber floorboards and then sand down the boards and use them as the finished floor, as if this was done then the flat below would suffer in regard to hearing footsteps (transmitted sound) and through the noise from the flat above coming through the floor (airborne noise).
There are also some leases that apply a similar logic that the noise of footsteps on the timber floor could also transmit to adjacent flats or flats above, but that is less common, but we will also look at measures to deal with those issues as well.
Since the lease agreements were written though the options to install timber flooring have increased and it is possible to install systems that can be demonstrated to adequately deal with the problem.
The original intention of these clauses was to ensure that the leaseholder did not simply remove the carpet and underlay laid on the timber floorboards and then sand down the boards and use them as the finished floor, as if this was done then the flat below would suffer in regard to hearing footsteps (transmitted sound) and through the noise from the flat above coming through the floor (airborne noise).
There are also some leases that apply a similar logic that the noise of footsteps on the timber floor could also transmit to adjacent flats or flats above, but that is less common, but we will also look at measures to deal with those issues as well.
Since the lease agreements were written though the options to install timber flooring have increased and it is possible to install systems that can be demonstrated to adequately deal with the problem.
The proposed solution very much depends on the construction of the floor between the two flats (in this case we are looking at the floor between the flat and the flat below)
Where flats have been converted from original houses, then the floor may be constructed as timber joists with plasterboard to the underside and floorboards on top, whilst there may be some insulation between the floor joists, such a form of construction provides very little in the way of acoustic separation and would not comply with the current Building Regulations for a new floor or where a flat is created by conversion of an existing building.
If this is the construction in place then removing the carpet would genuinely affect performance of the floor from an acoustic perspective. In such instances it would be necessary to look at removing the floorboards, reviewing the type and amount [if any] of the insulation between the floor joists and then installing an acoustic subfloor board and then lay a floating timber floor on top of this. Extra care is needed at junctions with walls to prevent what is known as flanking transmission where noise is transferred into the wall which then travels around the edge of the floor structure, as such it is necessary to acoustically separate the subfloor and floating floor from walls. The installation of such a system will raise the level of the floor and whilst this can be accommodated in a whole flat refurbishment where floor heights can be adjusted and new skirtings installed, it can be problematic in a limited scope of refurbishment regarding junctions with other rooms and existing doors, skirtings etc. An unintended consequence can be where changes in floor level mean that the height of window cills and balustrades above the finished floor level become lower than is advisable from a safety perspective, and also how raising the floor level can effect and existing stairs that are to be retained.
In many mansion blocks, the floor construction is a beam and pot concrete floor slab with a timber floor supported on timber battens. The underside of the slab is quite often plastered direct. In these instances there is potentially more scope to improve the acoustic performance of the floor using additional insulation between the battens, acoustic batten supports and acoustic sub-floor options.
Early engagement is essential before embarking on what could potentially be costly and time-consuming exercises.
Some freeholders will accept a proposal where manufacturers data is submitted to show that the proposed construction will perform as well acoustically as the previously carpeted room.
Others will require acoustic testing to be done, to establish the current performance, along with the submission of proposals to demonstrate how the level of performance will be maintained and then post completion testing to show that the system performed as well as was suggested.
Whereas others may allow the change to be made but retain a clause in the lease that would allow the works to be reversed if complaints, were received. In this instance it is sensible to look at how to minimise the potential for complaints, but there is still a significant risk in accepting such a clause and consideration should be given to investigating if the clause can be replaced to include a measurable benchmark in terms of acoustic performance.
Engaging a Chartered Architecture Practice ensures expert guidance on adding timber flooring to a leasehold property. They navigate lease restrictions, ensure compliance with building regulations, and create designs that enhance aesthetics and functionality. Their expertise minimises risks, secures approvals, and provides tailored solutions, delivering quality, value, and peace of mind.
BB Partnership have worked on projects on many of London’s major estates, including refurbishment and extensions to Grade I listed properties on the Crown Estate, Grade II Listed Buildings in The Grosvenor, Cadogan, and Wellcome Trust Estates as well as other projects on the Eyre Estate and Portman Estate, along with works to privately managed apartments, as such we are well placed to discuss the issues relating to the installation of timber floors and how this can be approached.
Our scheme in Albert Court was for the conversion of a former office into a high-end residential apartment.
The project involved the creation of a substantial lateral flat at first floor level in Albert Court, a Grade II listed mansion block looking west over the steps of the Albert Hall.
Previously used as offices, the scheme presented a number of challenges as part of the process to convert it into a high-end residential apartment, these included obtaining planning and listed building consent for the works as part of which comfort cooling was installed along with working with the freeholders team to carry out acoustic upgrades to the floors to facilitate the installation of stone and timber flooring.
BB Partnership worked in conjunction with interior designer Turner Pocock –www.turnerpocock.co.uk
In order to obtain freeholder consent to change the floor finishes to hard finishes it was necessary to arrange for acoustic testing to be carried out to establish the existing levels of performance with carpet in place. Interestingly the results demonstrated that the existing floor performed better than the requirements of the then current building regulations for conversion and the more onerous ones that related to new build properties. As such the system had to be designed to match the existing performance, further testing was then carried out to confirm that the installation performed as expected. This process required having to arrange access to the flats below the flat in question to carry out tests both before and afterwards. In this instance the system involved a floating finish on a subfloor supported on battens, which in turn were placed on an acoustic cradle system with insulation placed between the battens.
Reviewing the quality of a subfloor in a flat will also, invariably identify other issues that may need to be addressed. Quite often there are other penetrations in the floor that as well as acting as a conduit for noise are also compromising the fire safety of the floor, so carrying out these works does give the opportunity to address any other issues.
The upgrading of the acoustic performance of a floor is a two-way street, whilst the requirement stem from the need to satisfy a freeholder requirement, doing the works will result in improved acoustic separation from the flat below, allow for any unevenness in the floor to be improved and create a solid, sealed system.
The increased amount of insulation will also aid comfort in the property and reduce any drafts.
Cleaning out voids and sealing them will also prevent the ingress of dust into the property.
In a large refurbishment project, for example in a mansion block, the services generally run under the battened floor, so lifting it is a necessary event regardless of the acoustic aspects of the project, meaning that some of the costs associated with the works would be required regardless.
I hope that the above information has proved to be useful, at BB Partnership we believe that our experience of working on schemes all the way through to completion allows us to consider all aspects of a project at an early stage to ensure that our schemes can be successfully delivered.
Please contact us for more information.