The trustees of Sargent-Towne Estates Trust (landlord) brought these actions to review orders of the Boston Rent Board (board) which -denied general adjustments in the maximum rents for 352 controlled apartments owned by the landlord. The Boston Housing Court affirmed the orders of the board. We affirm the judgments of the Housing Court.
Sargent-T owne Estates is an apartment complex in Brighton which consists of eighty-eight small buildings containing four units each. In August and September, 1976, the Boston building department issued citations which notified the landlord that the main common entry doors of all buildings were not equipped to “close and lock automatically,” in violation of G. L. c. 143, § 3R. 2 On October 8, 1976, the landlord appealed these citations to the State Building Code Appeals Board (Appeals Board) on the ground that G. L. c. 143, § 3R, did not apply to these *454 buildings because they were constructed before its effective date. However, this appeal was withdrawn on November 12, 1976, for reasons not stated in the record.
On November 24, 1976, the board ordered a general adjustment increasing maximum rents for all controlled units, and on December 16, 1976, the board promulgated Regulation 11 to implement that order. “Regulation 11” provided that the adjustment would be effective January 1, 1977 (§ 12[D]), but that landlords would hold in escrow the amount of rents attributable to the increase until February 28, 1977 (§ 3[C]). It further provided that the adjustment would be “subject to the . . . condition” that “[a]s of January 1, 1977, the building . . . shall comply with all laws governing conditions of habitability” (§ 5[A][3]), and that, if this condition were not met, “the landlord shall not be entitled” to the adjustment (§ 5[B][1]) and that the board could order the landlord to refund to tenants any increase already collected (§§ 5[B][2], 6[A][l][b]).
On January 18, 1977, tenants of Sargent-Towne Estates filed an affidavit opposing the adjustment, see § 6(A) (1) (a), on the ground that the buildings were in violation of G. L. c. 143, § 3R. After several hearings on the matter, the board’s hearing officer found that there were no locks on the main common entry doors of any of the buildings, and that the Boston building department had determined those conditions to be in violation of G. L. c. 143, § 3R. On June 23, 1977, the board ruled that the buildings were not in compliance with all laws governing habitability, as required by Regulation 11, § 5(A)(3). Since the adjustment had been conditioned on such compliance, the board ordered the increase rescinded as to all units until such time as the landlord remedied the violations and obtained a certificate of compliance under § 9 of Regulation 11. In addition, the board ordered the landlord to refund to tenants the amounts held in escrow for the increase. At the request of the landlord, however, the board stayed its orders pending a decision by the Appeals Board on a renewed appeal which the landlord had filed on May 17, 1977.
*455 The Appeals Board held a public hearing on the issues raised by the landlord and thereafter obtained an opinion from the Attorney General regarding the applicability of G. L. c. 143, § 3R. On February 15, 1978, the Appeals Board adopted that opinion and ruled that the statute applies to all buildings containing the requisite number of apartments, including those constructed prior to its effective date. The Appeals Board also ruled that the statute does not require electric striker mechanisms on main common entry doors but requires only that such doors close and lock automatically. 3 However, due to difficulties presented by the “unique configuration” of these buildings, the Appeals Board granted a waiver of this requirement, as permitted by the statute, on the condition that the landlord install specified alternative systems which the Appeals Board found adequate to protect the tenants.
Following this decision, the landlord requested the board to vacate its prior order denying the general adjustment. After hearing, the board’s hearing officer found that the landlord had installed neither locks nor any of the systems required as a condition of the Appeal Board’s waiver. The hearing officer also construed the waiver to be prospective only. On March 23,1978, the board confirmed its order denying the rent increase and dissolved its prior stay of that order, thus requiring the landlord to refund the amounts already paid into escrow for the increase. The board ordered that rents be paid at the levels existing prior to the general adjustment until the landlord installed the systems required by the waiver and obtained a certificate of compliance from the board. It appears, however, that the landlord ultimately chose not to install those systems and installed locks with electric striker mechanisms instead. On June 22, 1978, after hearing and inspection, the board issued a certificate of compliance on these buildings and granted the general adjustment, effective July 1, 1978.
*456
On review in the Housing Court, the landlord challenged the board’s denial of the adjustment for the period January I, 1977, to July 1, 1978.
4
The tenants moved for summary judgment, and the board supported that motion. All three parties submitted documents and memoranda of law in support of their positions, but none of the parties submitted affidavits as permitted by Mass.R.Civ.P. 56(a),
1. The landlord’s principal argument in the trial court was that G. L. c. 143, § 3R, is not a law “governing conditions of habitability” within the meaning of Regulation 11, § 5(A)(3). In support of this argument, the landlord first points out that the statute was not incorporated in the State Sanitary Code on January 1, 1977, the operative date of the regulation. 5 However, G. L. c. 143, § 3R, had at that time long been incorporated in the State Building Code, 6 and that is sufficient to bring it within the scope of the implied warranty of habitability.
Recent opinions of the Supreme Judicial Court have made clear that the warranty includes, as a minimum, not only the requirements of the Sanitary Code but also those of the Building Code.
Crowell
v.
McCaffrey,
The landlord’s next argument is based on the Housing Court’s finding that “while the apartments were not rendered uninhabitable, certainly habitability was in fact affected.” The landlord suggests that since the absence of the locks required by G. L. c. 143, § 3R, did not render the apartments uninhabitable, the statute is not a law “governing conditions of habitability.” We disagree.
“Habitability” is a term of art, and an apartment need not be literally uninhabitable to be in violation of the implied warranty. The revised Sanitary Code, see note 5
supra,
draws a distinction between a condition, which makes a unit “unfit for human habitation” (defined as a condition justifying condemnation), 105 Code Mass. Regs. § 410.022 (1978), and a condition which “may endanger or materially impair the health or safety and wellbeing of an occupant” (defined as a condition which may expose those interests to harm), 105 Code Mass. Regs. § 410.023 (1978). The latter condition is sufficient to violate the warranty of habitability.
Boston Housing Authy.
v.
Hemingway, supra
*458
at 200 n.15 (proof that “Code violations exist which ‘may endanger or materially impair . . .’ would constitute evidence of a material breach . . .”). See also
id.
at 200 n.16. An apartment need not be totally uninhabitable before the implied warranty is violated. See
id.
at 202 (material breach may result in either “partial or complete” abatement of rent);
McKenna
v.
Begin,
Likewise, a statute which fixes minimum requirements for residential premises may have a direct and significant bearing on habitability even though a violation of the statute does not render the premises totally uninhabitable. Here, the Housing Court found that “certainly habitability was in fact affected” by the violations of G. L. c. 143, § 3R.
8
We cannot say that this finding is clearly erroneous.
9
Mass.R.Civ.P. 52(a),
*459
2. The landlord’s principal argument in this court is that the board lacked authority under the prevailing enabling statutes, St. 1969, c. 797, as amended by St. 1970, c. 863,
10
to condition the general adjustment on compliance with “all laws governing conditions of habitability.” The landlord also makes the related argument that the board lacked authority to deny the entire amount of the adjustment because such denial conflicts with the statutory requirement that landlords receive a “fair net operating income” from controlled units. St. 1970, c. 863, § 2. The defendants maintain, however, that the landlord never raised these contentions below. The record shows that the defendants are correct. In particular, we find no mention of these arguments either in the board’s summary of its proceedings or in the summary of issues set out in the Housing Court’s opinion. The landlord may not raise these issues on appeal where he failed to raise them in the trial court, see
Milton
v.
Civil Serv. Commn.,
Nevertheless, the landlord contends that those issues are “in substance the same” as those raised below (“albeit through expanded and somewhat differently formulated arguments”) and points to four isolated phrases in the amended complaint as support for this contention. However, even if we construed the amended complaint as raising the issues now argued, the landlord not only failed to pursue those arguments but, in fact, took a contrary position in its *460 memorandum in opposition to summary judgment. 11 Moreover, the Housing Court specifically noted, in passing, that the “[p]laintiff does not in fact contest the validity of Regulation 11.”
Ordinarily, the conclusion we reach above would end our analysis. We note, however, that the issues raised here present only questions of law, contrast Milton v. Civil Serv. Commn., supra; they have been briefed and argued by all parties, and they implicate the rights of numerous landlords and tenants beyond this case. See Royal lndem. Co. v. Blakely, supra. For those reasons, and because the result we reach is not changed by our analysis, we discuss for future guidance the landlord’s arguments that the board lacks authority to condition a general adjustment on compliance with laws governing habitability.
A. Rent control in Boston is currently authorized by St. 1969, c. 797, as amended by St. 1970, c. 863. 12 The 1969 statute was unusually brief and broadly authorized the city to “create a rent board and empower it to establish as the maximum rent[s] . . . such . . . amount[s] as may be necessary to remove hardships or correct inequities.”
Section 2 of the 1970 statute inserted language which specified that the city “may authorize the board by regulation to make such general adjustments in such maximum rents” (emphasis inserted) as may be necessary for the same purposes. Section 2 also provided that in making general adjustments the board “shall observe the principle of maintaining maximum rents ... at levels which will yield to landlords a fair net operating income,” which was to be *461 determined by giving “due consideration ... to the following, among other relevant factors: ... (5) substantial deterioration of the housing accommodations, other than ordinary wear and tear, or failure to perform ordinary repair, replacement or maintenance.” 13
The scope of the authority of such special enabling acts is limited to “only those powers which are expressly conferred by statute or necessarily implied from those expressly conferred . . . .”
Church
v.
Boston,
The considerations set out in factor (5), quoted supra, are clearly relevant to habitability, the subject of Regulation 11, § 5(A)(3). The landlord argues, however, that factor (5) applies only to a “deterioration” of the premises from its previous condition, or to a lack of “repair, replacement or maintenance” regarding existing facilities. Thus, the argument continues, factor (5) does not apply to a “failure to install fixtures” which had never previously been provided, and Regulation 11, § 5(A) (3), therefore exceeds the scope of factor (5) to the extent that such devices would be required to comply with “all laws governing conditions of habitability-”
We have no difficulty in determining that the board had authority under factor (5) to promulgate Regulation 11, § 5(A) (3), requiring compliance with laws governing conditions of habitability. Although we find no Massachusetts cases which guide us in our construction of the criteria set out in factor (5), cf.
Sherman
v.
Rent Control Bd. of Brookline,
Section 2 of the present Boston statute is based on the prior Statewide enabling act, St. 1953, c. 434, § 5(a), which was derived in turn from the Federal Housing and Rent Act of 1949, c. 42, § 203(b), 63 Stat. 18 (1949). As relevant here, the provisions of these three sections are “substantially identical,” see
Marshal House, Inc.
v.
Rent Control Bd. of Brookline,
*463
Where an amendment actually incorporates into a statute the precise language of a regulation which sets out the administrative construction of the statute, that enactment constitutes an express ratification of that construction. See
United States
v.
Leslie Salt Co.,
Following the expiration of the Federal act, Massachusetts continued to control rents under St. 1953, c. 434. Although one section of that statute was held constitutional,
Russell
v.
Treasurer & Recr. Gen.,
Recently, however, the exercise of regulatory power under a rent control statute has been upheld on a different basis. In
Flynn
v.
Cambridge,
Under reasoning of the
Flynn
case, we think that the present statute, which contains an express policy favoring “repair, replacement or maintenance” of rental units, must be construed as giving Boston at least the general authority to link a rent increase with habitability, since that power is necessary to preserve the
quality
of its rental housing stock. New Jersey has specifically approved a rent control law which includes such a regulation. In
Orange Taxpayers Council, Inc.
v.
Orange,
The reasoning set forth above strikes us as sound. The fact that the Legislature included in the Boston statute a policy favoring maintenance of housing conditions suggests that it also shared these concerns. Cf.
Berman & Sons
v.
Jefferson, supra
at 198-199 n.4 (noting “legislative judgment” that tenant’s duty to pay rent is “bound up with” landlord’s duty to maintain premises, as manifested by enactment of G. L. c. 239, § 8A). We therefore hold that it is necessarily implied that the board has at least the general authority to tie a rent increase to compliance with laws governing habitability. Contrast
Babson
v.
Boston Rent Control Admr.,
B. The landlord next argues that the board lacked authority to promulgate § 5(A) (3) of Regulation 11 in so far as the denial of the entire amount of a general adjustment conflicts with the landlord’s statutory right to receive a fair net operating income. See
Zussman
v.
Rent Control Bd. of Brookline,
*466
The landlord does not suggest, however, that the amount of the increase which the board actually granted (although conditionally) was insufficient to constitute a fair net operating income. Nor does the landlord contend that the board, in fixing that amount, erred in failing to consider any of the factors set out in the statute. Rather, the landlord’s objection is to the emphasis which § 5(A) (3) of Regulation 11 places on factor (5). The short answer to this objection, however, is that the “statute provides no formula for ascribing relative weights to these factors,” and “substantial discretion is left with [the board] in deciding . . . what rent adjustments are to be allowed,”
Sherman
v.
Rent Control Bd. of Brookline,
*467
While the views embodied in a regulation do not bind us where its very authority is in issue, see
Niles
v.
Boston Rent Control Admr.,
In addition, we do not think that § 5(A) (3), abrogated the landlord’s right to a fair net operating income. Rather, it merely delayed the commencement of the adjustment, in effect leaving it up to the landlord to determine when it would begin. Analytically, the situation here is not unlike that presented in
Grace
v.
Brookline, supra.
There it was held that the town’s denial of certificates of eviction to all condominium developers furthered the statutory purpose of preserving the supply of rental units by “retarding” conver
*468
sion to condominiums, but also “fairly accommodate[d] the interests of building owners” in so far as it did not “preclude condominium conversion altogether.”
Id.
at 51. Likewise here, the board has not precluded the landlord from “any possibility” of receiving a fair net operating income. See
Orange Taxpayers Council, Inc.
v.
Orange,
3. The landlord also makes a series of arguments based on what is said to be the reasonableness of its actions here. The landlord first argues that it could not reasonably determine what equipment was required by G. L. c. 143, § 3R. It is apparently true that on May 10, 1977, the Boston building department reversed its prior position and adopted the view that the statute required electric striker mechanisms. But there is nothing in the record to establish that the landlord had previously made any effort to comply with the statute during the nine months when the building department agreed with the landlord as to its requirements. Nor did the landlord subsequently install even the locks which it believed to be required (and which were ultimately held to be required) during the pendency of its action before the Appeals Board. The fact of the matter is that the landlord was never in compliance with-the statute during the period for which the general adjustment was denied. For that reason, such denial was not error.
As to the other arguments based on the alleged reasonableness of the landlord’s actions, we conclude that they either lack merit or raise no question of law not already considered above.
4. Finally, the landlord alleges a number of procedural defects in the board’s proceedings. We think that the ten
*469
ants’ affidavit in opposition to the adjustment was properly processed under § 6(A)(1) rather than § 6(A)(2) of Regulation 11. As to the landlord’s other allegations, we need not deal with them individually, because all of them are without significance in the present circumstances. See
Niles
v.
Boston Rent Control Admr.,
Judgments affirmed.
Notes
General Laws c. 143, § 3R, inserted by St. 1965, c. 464, § 1, and as amended through St. 1974, c. 541, § 13, provides in pertinent part as follows: “At least one of the doors of the main common entryway into every apartment house having more than three apartments shall be so designed or equipped as to close and lock automatically with a lock, including a lock with an electrically-operated striker mechanism, a self-closing door and associated equipment, and such lock, door or equipment shall be of a type approved by the state building code commission .... provided, however, that the said commission may, in writing, waive . . . [this] requirement... in appropriate cases in which, in its opinion, other security measures are in force which adequately protect the residents of such apartment house.”
The Appeals Board found that the doors at issue here “do not have locks but do have self closing devices.”
The landlord filed one action to review the board’s order of June 23, 1977, and another action following the order of March 23, 1978. The landlord moved to consolidate the two actions, and that motion was apparently allowed, although the docket does not so reflect. In addition, the tenants were joined as defendants by order of court.
At that time, the Sanitary Code was silent regarding requirements for locks. Shortly thereafter, however, on August 1, 1977, a revised version of the code added a new section entitled “Security,” which incorporated the portion of the statute relevant here. 67 Mass. Reg. 21, 34 (1977). This regulation is now codified as 105 Code Mass. Regs. § 410.480(C) (1978).
See § 612.411 of the State Building Code, as filed with the State Secretary on July 1, 1974, effective January 1, 1975. That regulation is now codified at 780 Code Mass. Regs. § 612.5.1.1 (1979).
We therefore do not decide whether the statute standing alone would fall within the scope of the implied warranty or of Regulation 11, § 5(A)(3).
It is worth noting, however, that the implied warranty gives landlords a general obligation to maintain the premises in safe condition. See
Crowell
v.
McCaffrey, supra
at 446-448 (summarizing recent case law). See also
Javins
v.
First Natl. Realty Corp.,
The landlord contends that the scope of Regulation 11, § 5(A)(3), will become indefinite and unpredictable if we construe a statute as “governing conditions of habitability” where habitability is merely “affected.” Whatever the merit of this argument in another context, we think that it has no application here. We read the emphasis contained in the judge’s language above as indicating a finding that habitability was, in fact, materially affected. Moreover, as discussed supra, the fact that the statute at issue here was incorporated in the State Building Code undercuts any argument that its bearing on habitability was indefinite in the present case.
See 105 Code Mass. Regs. §§ 410.700, 410.750 (1979), inserted in compliance with St. 1973, c. 880, amending G. L. c. Ill, § 127A. Although § 410.750 of the Code, see note 5, supra, does not include the absence of a lock on an exterior door as a condition which “shall always be deemed” a serious violation, that section emphasizes that such omission “shall in no way be construed as a determination that. . . [it] may not be found to fall within” that category. See also § 410.700.
During the period when the Statewide enabling act was in effect, Boston conducted rent control pursuant to the authority of that act. St. 1970, c. 842. Since the expiration of that act on April 1, 1976, rent control has continued in Boston under the authority of the original enabling statute for that city.
Since both the landlord and the tenants refer to this memorandum, and it was not included in the record on appeal, we have exercised our discretion to send for the original papers in this case. See
Ainslie
v.
Ainslie,
Both of these statutes were based on a legislative finding that there was a “substantial shortage of rental housing” and that residential rents must be “regulated and controlled” in order to avoid “serious threats to the public health, safety, and general welfare.”
Two of the other factors to be considered in determining fair net operating income are as follows: “(3) major capital improvement of the housing accomodations as distinguished from ordinary repair, replacement and maintenance; (4) increases or decreases in living space, services, furniture, furnishings or equipment . . . .”
The Emergency Price Control Act of 1942, c. 26, § 2(b), 56 Stat. 23, and the Housing and Rent Act of 1947, c. 163, § 204(b), 61 Stat. 193, which superseded the 1942 Act as the authority for controlling rents. *463 Ultimately, in 1949, the 1947 Act was amended to insert the provision dealing with fair net operating income which also appears in the Boston statute. In so doing, Congress adopted the language of the prior regulations and incorporated it into the fourth and fifth factors to be considered in making that determination. See Regulation § 1388.1181, Rent Regulation for Housing §§ 5(c)(2) & 13(7), 8 Fed. Reg. 7322 (1943); Regulation § 825.10, Controlled Housing Rent Regulation §§ 1 & 5(a) (2), 12 Fed. Reg. 4331 (1947). These regulations were formerly codified at 24 C.F.R. §§ 825.1 & 825.5(c)(2) (1947 Supp.).
It is generally the rule in this jurisdiction to adhere to the Federal construction of Federal legislation which is subsequently incorporated in a Massachusetts statute. See
Poirier
v.
Superior Court,
The board may have learned from experience that where only a small percentage of an increase is withheld, the landlord lacks sufficient incentive to make the necessary repairs, particularly where the cost of the repairs would exceed the amount withheld, in which case the landlord might well decide to forgo both the remainder of the increase and the repairs.
Although the parties do not raise this point, we note that the Massachusetts Legislature has enacted such a provision in several other rent control enabling statutes. That provision, with slight variations, states that “[t]he board . . . may refuse
to
grant a rent increase under this section, if it determines that the affected rental unit does not comply with the state sanitary code and any applicable municipal codes, ordinances or by-laws, and if it determines that such lack of compliance is due to the failure of the landlord to provide normal and adequate repair and maintenance.” St. 1970, c. 842, § 7(d) (Statewide act); St. 1976, c. 36, § 7(d) (Cambridge); St. 1976, c. 37, § 5(d) (Somerville). See
Palmer
v.
Rent Control Bd. of Brookline,
However, since the Boston statute was adopted under the Home Rule Amendment,
Church
v.
Boston,