Building renovation or new construction?


Usually presented to the public this issue as political dilemma between two mutually exclusive alternatives. But we should clarify what actually is being discussed. and what does each of the two options.

Firstly, the concept of rehabilitation of housing is very broad and can include responding to diverse needs: structural rehabilitation and construction of buildings, the use of common areas, the implementation of renewable energy and plans energy efficiency, economic management of the property owners, funding, finding possible sources of income, housing development, management of common services and many others. In short, everything is matter (or not) of a housing policy.

In this regard, a housing policy that has rehabilitation as one of its priority objectives should define its own comprehensive strategy in relation to these needs. But these needs are manifested in the form of a multiplicity of situations and solve problems that require a broad and solid repertoire of solutions. In no case should be based on a technical assumption a priori (rehabilitation or new construction, for example) but the technical solution should be the consequence of that policy.

Perhaps, therefore, we should reserve the term 'rehabilitation' to designate a policy, but not to designate a particular technical solution in a particular case. Would not it be better to speak of 'repair' of a building, instead of talking about his 'rehabilitation'? 'Replace' building a new plant is a technical solution that excludes and opposes its 'repair'. But not necessarily contradict a policy of rehabilitation.

That is, a housing demolished and rebuilt it with new plant is also 'rehabilitate' homes, if this decision is the result of the application of the guidelines for a political commitment to rehabilitation. And even resulting shocking or controversial, should be described as 'rehabilitation' also the replacement. This is legitimate, provided that justify the decision is a result of the application of previously established criteria, which are precisely the 'rehabilitation policy'. And we show the overall results of this policy, which this replacement would be integrated into a set of actions. For example, repair and reconstruct buildings 85 15, it not sufficiently demonstrated the intent and purpose of a housing policy? Or: to promote the construction of new plant, is it not also 'rehabilitation', if it is to consolidate a neighborhood with a compatible use?

The term 'promote' is a term now discredited, and rightly so, given the connotations and links with speculation, with the destruction of the environment, etc. But in the same way that should untie the terms 'rehabilitation' and 'repair' should also dissociate the terms 'promotion' and 'new'. In short, it is only possible policy for the rehabilitation of homes if there is an ambitious strategy of "promoting rehabilitation," the experience and techniques of residential development.

Accordingly, before discussing if necessary repair or replace a building should define what is the goal of housing policy, under which we face this particular problem.

When we study the option is more favorable in a specific case, we can certainly apply the concept of ruin technique, which is not a bad approach, which already has a long legal: if the cost of repair exceeds 50% the replacement cost, then it is not worth repairing. But while the economic assessment of the reconstruction of a building operation is generally sufficiently reliable valuation of repair is subject to many variables, often uncertain. Essentially, there are two: first, the evaluation of the condition of the building; on the other, defining benefits is required, once repaired.

If the evaluation of the condition of the building and defining its benefits are based on the requirements established by current legislation, it is clear that repair is not often a good choice. In fact, this event starting most of our buildings must be ruined technique. Therefore, the assessment of the repair should be based on the fixation of the performance should have the building repaired.

In general, there is general consensus on the benefits of energy efficiency or accessibility. And, of course, respect the stability and safety of the structure. But a little deeper into these issues easily reach uncertainties and contradictions. Especially when compared to the performance required in the building repaired with the majority of existing buildings.

This, then, is the key issue: to define the performance we demand the building repaired. And unfortunately this 'program needs' not on the commission to measure the cost of repair by a technical team. It's not enough to refer to current legislation, which provides many doubts of interpretation in applying existing buildings.

For example, what is the safety factor required in the structure of an existing building? Well, we all agree: the structure must be safe and stable. But this, what does it mean? A safety factor equal to 1.0? A 1.2? Or 1.6? When a building falls, and it is Perita and I had a coefficient equal to 0.83. For this fall. Whoops! Will, on the contrary, the collapse of the building is the cause of this ratio?

Appraise the structure of a building is not easy. It asks that the coach is not asked a doctor: proving with his signature that his patient will die within the next ten years. But what estimation of loads 'reasonable' to do? How many tests and preliminary tests must order? What safety factor should adopt? Current legislation in the case of existing buildings, does not answer any of those questions. And if you stick to their literal, then the repair is never a good option.

The administration has set what must be the performance of the building repaired, if you want to apply a consistent policy of rehabilitation. To do this, it must write new laws. Most laws do not, for God's sake! Simply, should design its own strategy, but must do so with determination and commitment: with intent. He put his own bar, the level of which is determined by a criterion that determines everything: the economic viability of its policy. Only thus can achieve results, which will be models for the private sector.



Issue 1 (11/17/2018)

Written and approved by

Joaquim Iborra Posadas