Screed
The laying of a screed and the subsequent bonding of stoneware
In this house in Vicenza, we first made the traditional sand and cement screed, which was smoothed by hand, and after about 20 days we laid a floor of porcelain stoneware tiles by bonding using the double-spreading technique.
When a screed is required
It is necessary to install a screed in a new house or in a renovation if you decide to demolish both the floor and the layers underneath, for example if you decide to redo the plumbing and electrical system.
In other cases, the new floor can be laid on top of the existing floor. Clearly, in these cases, it is necessary to bear in mind that the level of the finished floor will be higher than the existing floor and to resolve any related problems. For example, raising or modifying internal doors, checking the possibility of modifying the entrance door (armoured doors are more complex to modify) as well as French doors to access external terraces, etc.
There are cases in which the customer is prepared to do either an overlay or a total refurbishment and asks us for advice on which route to take. If both options are feasible, a new screed is far preferable. The new screed will guarantee a perfectly flat, compact surface with the right grip. These are all conditions that are difficult to achieve on an existing floor, which - especially if made several years ago - may not be flat and may have concave or convex portions. In short, the floor is certainly better on a new screed.
Who should make the screed?
There is a growing tendency to outsource the screed to "specialist teams", but is this the right solution? In our opinion, it is not, at least not if you want to protect the end customer from problems. The screed, in fact, is destined to become an integral part of the floor that we will glue on top of it. Floor and screed are complementary elements that become one. Having them made by two different (legal) parties subjects the end customer, i.e. you reading this, to a very high risk of future "blame-shifting" in the event of problems.
Our advice is that you choose - carefully - ONE partner for the screed and the floor, as they are intimately connected.
In this way you will avoid most of the possible future problems. If you want to get to grips with all the possible problems that can happen to a floor, well, here are the main ones:
problems and diseases in floors
The saying goes: "If you know them, you avoid them".
How do I choose the screed/floor layer?
I think I have conveyed to you the importance of choosing a single point of contact. But also involve your project manager in this reasoning (he takes a bigger risk than you do when framing the work) and if that's not enough, talk to other customers who have had work done before you.
Also read the references on Google or on social networks and maybe talk to some clients who have chosen a contractor you like.
When you've made up your mind, ask that the two jobs (screed and floor) are both invoiced by the same company, preferably with the wording: "contracted out to...". Someone could avoid future responsibilities by convincing you that the invoice will be issued directly by the screed installer or a third party company: do not accept this.
With a single interlocutor you will be much better protected and there will be no doubt - in the unfortunate event of problems - as to who should be responsible. Also be wary of anyone who simply sells you the materials and invoices them separately from the installation (large retailers, for example, always do this).
And, I repeat, don't be fooled by the savings of a few euros that you can obtain by entrusting the screed to a company that only makes screeds.
The correct reasoning that you should do is to multiply the few euros saved by the surface area to be paved (you spend 2 euros less and you have 100 metres of house? That's just 200 euros...) and then consider the consequences of this "saving" in terms of time lost by you in coordinating two different operators: screeders and installers.
Not to mention, as mentioned, the blame game in case of problems.
Which screed to choose?
We have dedicated a series of articles to the various types of screed available today.
The first article I recommend you read is this one, which contains the basics:
1. General characteristics of the screed
If you feel the need to go deeper into your specific case, I recommend reading these other articles that deal with specific situations.
For example: if you have to lay ceramic tiles, you should read this article:
2. The traditional sand and cement screed for laying tiles
If you are planning to install an underfloor heating system, you will find a very comprehensive article on this type of screed here:
3. The screed on underfloor heating
Parquet requires more attention and the screed for wooden floors will therefore have different requirements and characteristics. Here is the information:
4. The traditional screed for laying wooden floors
The self-levelling screed has grown rapidly to become one of the most widely used screeds. But it is not always the right choice. If you are planning to have a self-levelling screed made, you should read:
5. The anhydrite-based self-levelling screed
If your problem is weight, perhaps because you don't want to make the floors of your house too heavy, there are solutions that allow you to make lighter screeds.
But you might want a quick-drying screed, a dry screed... there are still many types available to choose from.
Screeds: other things to know
There are elements of the screed that seem to be of minor importance, but can also seriously affect the durability of the floor:
Read also: joints in the screed
Read also: the vapour barrier
Read also: the perimeter strip
Checking the screed
Let's assume that you have chosen the traditional sand and cement screed (our favourite!). How long before the floor can be laid? Are there any checks to be made before proceeding? We have discussed this in the following article:
Read also: checks to be made on the screed
Laying the screed and dry "presentation" of the tiles
After creating the screeds, we carried out the checks in this private house in Vicenza and were ready to lay the wood-effect stoneware tiles. We laid them on the floor to "present" the final effect to the customer. This is a fundamental operation that should always be done before starting with the laying.
The dry presentation allows the customer (or the project manager) to approve the continuation of the installation or to stop it before it starts, if the floor is not the one chosen or if there are last-minute changes of mind.
Once the floor has been laid, it is very difficult to go back...
External screed
If the screed is to be laid outdoors, it must have certain characteristics that differentiate it from an indoor screed. For example, it must have a suitable slope to allow water to drain off and it must be protected in order to last longer.
Read also: screed protection